Passengers on a Singapore Airlines flight hit by severe turbulence on Tuesday described a sudden, dramatic drop as 鈥渁ll hell broke loose鈥 on board the Boeing airliner carrying 229 passengers and crew.

At first, 鈥渢he flight was perfectly normal,鈥 said passenger Andrew Davies, who was traveling to New Zealand for business. He described the flight as 鈥渜uite smooth 鈥 I don鈥檛 remember any turbulence at all.鈥

Flight SQ321 was cruising at 37,000 feet from London to Singapore when flight tracking data shows the plane dropped sharply before climbing several hundred feet, then repeated the dip and ascent, for about a minute.

Many passengers were having breakfast at the time of the incident.

Then, about nine or 10 hours into the roughly 13-hour flight, he was watching a movie when he saw the seat belt sign light up 鈥 so he put his seat belt on. 鈥淭hank goodness I did because within moments of doing that, all hell broke loose,鈥 he told CNN鈥檚 鈥淓rin Burnett OutFront.鈥

鈥淭he plane just felt like it dropped. It probably only lasted a few seconds, but I remember vividly seeing shoes and iPads and iPhones and cushions and blankets and cutlery and plates and cups flying through the air and crashing to the ceiling. The gentleman next to me had a cup of coffee, which went straight all over me and up to the ceiling,鈥 Davies said.

Images from the plane afterward show the cabin in disarray, with papers, cups and water pitchers scattered on the floor, and ceiling panels and piping hanging loose.

Davies was sitting toward the front of the plane and witnessed some of the injuries sustained by dozens of passengers 鈥 including Geoff Kitchen, a 73-year-old Briton who died on the flight.

鈥淭hat gentleman was sitting right behind me,鈥 he said. 鈥淟ots of people needed some help but we tended to this gentleman, and I helped carry him, get him out of the seat, and we laid him on the floor so that some medical professions could administer CPR.鈥

Kitchen was given CPR for about 20 minutes, said Davies. Meanwhile, he said, 鈥渢here was so much screaming,鈥 and people鈥檚 injuries were evident; when he turned around, he saw one passenger with 鈥渁 big gash in her head and blood pouring down her face,鈥 and another elderly passenger in 鈥渟evere shock.鈥

Another passenger, 28-year-old student Dzafran Azmir, told Reuters that the aircraft had begun 鈥渢ilting up鈥 and shaking.

鈥淰ery suddenly there was a very dramatic drop so everyone seated and not wearing a seatbelt was launched immediately into the ceiling,鈥 he told Reuters. 鈥淪ome people hit their heads on the baggage cabins overhead and dented it, they hit the places where lights and masks are and broke straight through it.鈥

Azmir added that the whole thing was 鈥渞eally, really quick 鈥 which is why I think nobody could really respond to it.鈥 People didn鈥檛 have time to react, he said 鈥 there were passengers in the plane bathrooms and air crew still standing when the turbulence hit.

The plane was diverted to Bangkok after the incident, which injured 104 of the passengers, according to an update at Wednesday lunchtime from the Samitivej Srinakarin Hospital, which treated many of the travelers.

Those injured on the flight included citizens from Australia, Malaysia, the United Kingdom, New Zealand, Spain, the United States and Ireland, the hospital said in an earlier update.

Those needing medical assistance were sent to several hospitals in the Thai capital, while others were looked after at a clinic at the airport. Samitivej Srinakarin Hospital said 20 travelers remained in intensive care units on Wednesday.

Josh Silverton, one of the passengers on the Singapore Airlines flight, described feeling 鈥渉appy to be alive鈥 as he was leaving Samitivej Srinakarin Hospital on Wednesday evening.

Speaking with journalists on his way out, the 24-year-old British citizen said he had suffered a cut on his eye and a chipped tooth in the turbulence.

He also said that after the incident had taken place, he had let his mother know he was ok by purchasing an in-flight Wifi package for the first time in his life.

Silverton described the aftermath of the emergency landing in Bangkok, saying he started vomiting, which prompted him to look for medical care.

According to Silverton, there are still several passengers being treated at the hospital, many apparently with spinal injuries and in a much worse physical state than he is.

Silverton told journalists he was 鈥済oing to Bali to see my boys鈥 when the horror on SQ321 unfolded, but he still hopes to eventually get there.

Of the 211 passengers and 18 crew on board the original flight, 143 were transported via a relief flight to Singapore, where they landed early Wednesday morning, according to Singapore Airlines CEO Goh Choon Phong in a video message released on Facebook.

The remaining 79 passengers and 6 crew members are still in Bangkok, including those receiving medical care, and their family members.

Kittipong Kittikachorn, the general manager of the Bangkok airport, said on Tuesday that preliminary investigations suggest Kitchen had suffered from a heart condition, and that the autopsy process is ongoing.

Several passengers had broken arms, but the majority of injuries were cuts and bruises, he added.

Goh, the CEO, extended his condolences to Kitchen鈥檚 family and loved ones, saying the airline was 鈥渄eeply saddened by this incident鈥 and was 鈥渧ery sorry for the traumatic experience鈥 that passengers endured.

The airline is cooperating with authorities on the investigation, he added.

Singapore鈥檚 Ministry of Transport is investigating the incident, saying Tuesday it was in touch with its Thai counterparts and would be sending investigators to Bangkok. The US National Transportation Safety Board is also sending personnel to Singapore to help the investigation, including a representative of the board and four technical advisors.