DUBAI, United Arab Emirates -- Thick seasonal fog again has engulfed parts of the United Arab Emirates, delaying flights and causing car crashes.

The UAE's National Center of Meteorology & Seismology said Thursday that visibility dropped below 50 metres (55 yards) in some areas.

Dubai International Airport, the world's busiest for international travel and home to long-haul carrier Emirates, saw flight delays. Delays also hit Abu Dhabi and Sharjah's international airports.

Dubai police said heavy fog caused 119 traffic crashes Wednesday and 107 on Thursday.

Separately, Abu Dhabi police said on Twitter a car crash killed five people near Liwa, without elaborating on the cause or saying if the fog played a factor.

High humidity and falling temperatures cause the fog to roll in seasonally along the coast of the Arabian Peninsula.