Ukrainian civilians have been fleeing their country after Russia launched a full-scale invasion this week, with heavy artillery, missile strikes and troop mobilization in a multi-pronged ground assault across vast swaths of the country.

The move by Russian President Vladimir Putin is the largest conflict on the ground in Europe since the Second World War, and has been countered by Ukrainian President Volodymyr Zelensky cutting diplomatic ties with Russia, declaring martial law and ordering a full military mobilization set to last 90 days.

Russia far outstrips Ukraine in military terms 鈥 from raw numbers of troops to tactical gear and weapons.

According to Global Firepower, which analyzes data from 140 global military powers, Russia currently has 850,000 active personnel in its military, while Ukraine has 200,000. Russia also has five times as many tanks and two times as many armoured vehicles than Ukraine

Despite the numbers, Ukraine is determined to fight.

As Russian tanks roll towards the capital city of Kyiv, CTVNews.ca has interviewed leading military experts to explain how the invasion of Ukraine could potentially unfold on various fronts.

LAND

Keir Giles, an expert on the Russian military, told CTVNews.ca that Russia has spent a decade investing trillions into transforming its armed forces, and learned from their 2008 invasion of Georgia where their fine-tuning was needed.

鈥淭his has been an ongoing process, which has been refined by Russia鈥檚 experience of combat in Syria and in Ukraine itself,鈥 Giles, senior consulting fellow of the Russia and Eurasia Programme at Chatham House in the U.K., said in a telephone interview Friday. 鈥淪yria in particular saw Russia testing out weapons systems, organizations, personnel [and] logistics.鈥

Giles said Russia鈥檚 core strengths lie in 鈥渢raditional muscle,鈥 with emphasis on artillery and missile strikes from a distance that deliver 鈥渁 huge punishing impact on the enemy before closing in for combat.鈥

Russia鈥檚 multi-pronged attack has seen troops move in from the north from Belarus and capture the nuclear plant of Chornobyl and the surrounding area, as well as advancements from the east out of separatist-controlled areas in Donbas and strikes from the south out of the Black Sea and Azov Sea into port cities of Odesa and Mariupol.

Troops are now reported to be heading to Ukraine鈥檚 capital city, Kyiv.

Russia also has a notorious reputation when it comes to mercenary and private militias, such as the Wagner Group, which has been described by the U.S. government as a proxy force for the Russian military and has been accused of committing human rights abuses across Africa.

鈥淲e did see that elements of Wagner鈥檚 forces were being withdrawn from Africa ahead of this conflict in Ukraine, and the suspicion was that they were being prepared for missions in Ukraine itself. We've also seen that Russia is undertaking sabotage missions behind the lines, which unconventional forces would expect to be used,鈥 Giles said.

There have been being used in the assault on Ukraine yet.

鈥淎nother one to watch is the Chechen forces that are even more renowned for their brutality than the Russian main force,鈥 he continued. 鈥淩ussia would like Ukrainians to know that they are being prepared to be moved in, this is a terrifying prospect for anybody with experience of the medieval viciousness of Russian war fighting, as was demonstrated by both sides in the Chechen conflict.鈥

There have been being seen on the ground in Ukraine, with Chechen state TV saying leader , a staunch Putin ally, had .

SEA

The Russian Navy is generally organized into four combat forces: surface forces, the submarine forces, naval aviation and coastal troops.

鈥淭he Russian military is a very capable, very organized, very disciplined military. Whatever it decides to put into action is credible,鈥 retired vice-admiral and former vice chief of defence staff Mark Norman told CTVNews.ca. 鈥淭he challenge from a naval perspective as we look at Ukraine is it's all very tightly contained in the Black Sea.鈥

鈥淪hip-launched cruise missiles that can go a very long distances鈥undreds of kilometres,鈥 Norman said in a telephone interview Thursday. 鈥淚t appears clear that there's going to be a focus on infrastructure and on what we characterize as command and control of sea ports, rail heads those kinds of things which allow [Ukraine] to move their forces around and defend their territory,鈥 he said, adding that it is 鈥渢extbook鈥 for an attacking force to seize and hold a port to establish a staging point or 鈥渂eachhead.鈥

The Black Sea itself poses its own challenges, described by Norman as a 鈥渞elatively shallow body of water鈥 that has only one way in and out which makes it difficult to resupply or reinforce naval units, but plays to the Russian鈥檚 advantage when it comes to submarines.

鈥淚 would argue that the potential for Russian submarines in the Black Sea is probably the most significant aspect of what could happen because of the inherent advantages,鈥 Norman explained, adding that because the Black Sea is not particularly deep submarines do not have many places to hide, but poor acoustic conditions mean they do not have to hide in the same way they would in the open ocean or deep water.

AIR

The Russian Air Force is another branch of the military that has seen significant investment and experimentation over the years, Giles said.

Russia has 10 times the number of fighter aircraft and approximately 16 times the number of attack helicopters than Ukraine.

Russian air strikes have been bombarding major cities in Ukraine, including Kyiv.

According to the Pentagon Thursday, Russia has into Ukraine from Belarus, Russia and the sea.

The bombardments continued into the early hours of Friday morning ahead of reports of Russian tanks moving towards the capital.

鈥淥ne lesson that has been learnt from Syria is that we should not accuse Russia of being careless and indiscriminate with whom it bombs,鈥 he said, explaining that what was thought to be careless selection of targets that ended in civilian casualties was in fact 鈥渄eliberate policy.鈥

鈥淭here is no discrimination in terms of who will be a target in this war on Ukraine,鈥 he said.

According to associate professor of political science at Rutgers-Camden University in New Jersey, Michael Boyle, drones may play a significant role in the conflict.

鈥淚 would expect there to be the use of tactical drones with Russian ground forces as they try to seize more territory,鈥 he said in a telephone interview Thursday, adding they could be deployed in advance as a surveillance tool for ground forces.

There has been much divide over the use of drones in warfare, as targeted strikes from devices like the U.S. Reaper drones have limited success in hitting their intended targets and have been the cause of civilian deaths in Afghanistan and .

Boyle said if the Russians stick to using surveillance drones, the risk to civilians remain lower, but if they shift to doing targeted strikes, 鈥渢here are real concerns about the level of civilian casualties and the accuracy.鈥

CYBERATTACKS

Cyberattacks targeting the websites of Ukraine鈥檚 defence, foreign and interior ministries preceeded the Russian invasion, with massive distributed-denial-of-service (DDOS) attacks and malware.

Cyberattacks have been a calling card of Russian tactics over the past decade, with hackers trying to sow panic, thwart elections and cost millions of dollars in damage to infrastructure, business and commerce globally.

According to Brett Callow, threat analyst for Emsisoft, an anti-virus software company known for decrypting ransomware attacks, the cyber situation is 鈥渦nprecedented鈥 with the invasion of Ukraine.

鈥淎nything and everything is on the table,鈥 Callow said in a telephone interview with CTVNews.ca Thursday. 鈥淭here鈥檚 been an ongoing Russian cyber campaign against Ukraine for about a decade, what is happening at this point will be have been pre-planned for weeks, if not months 鈥 this will not be spur of the moment.鈥

Callow said Russia鈥檚 predetermined strategy will most likely involve a number of elements in its attack including intelligence gathering, Ukrainian military supply and response as well as psychological operations (known as 鈥榩syops鈥) against the Ukrainian military and the Ukrainian people.

鈥淯nfortunately at this point it's quite likely the Ukrainian system is widely compromised, and vulnerable to disruption. The Ukrainian government estimates that 40 per cent of the Microsoft software that they use is pirated,鈥 Callow said, adding that pirated software often comes with malware that can steal credentials to gain access to targeted networks, an MO Russian ransomware gangs have used in the past.

PROPAGANDA

Another major tool in Russia鈥檚 arsenal is the highly engineered stream of misinformation and propaganda, according to Boyle.

鈥淲hat we tend to see with Russian disinformation is that it is semantic, and what you start to see is that multiple outlets start to promote the same four to five arguments at the same time,鈥 Boyle continued, adding that Russia is not concerned with convincing skeptics as much as creating an air of plausibility with videos and stories from on the ground in Ukraine.

鈥淚t's hard to deny a crushed drone, for example. It's hard to deny bodies laying the ground, people crying and evidence of fires,鈥 he said, adding that further investigation of similar videos in the past has shown they were recorded days before the events allegedly occurred.

Boyle said the Russian propaganda and disinformation network is vast, organized and has found ways to use bot accounts to inflict a high degree of damage.

鈥淥ne thing Russia鈥檚 been very good about doing is laundering their messages so that they come in looking from superficially plausible feeds,鈥 he said, adding that in the 2020 U.S. election Russian disinformation campaigns got around Facebook filters by planting stories with Americans and American organizations that parroted messages from the Kremlin through a series of bot nets.

鈥淲e know they're going to amplify these false messages,鈥 he said of the Russians鈥 use of bot nets creeping into social media feeds of North Americans. 鈥淗ow do you stop that from taking hold on social media and then how do you particularly manage and police that when it's coming from people who have the right to free speech?鈥

----

With a file from CTVNews.ca鈥檚 writer Maggie Parkhill and data journalist Deena Zaidi