Travel to East Africa came to a halt this morning as fire raged for several hours at the Jomo Kenyatta International Airport in Nairobi, suspending international arrivals traffic on Wednesday. Most international flights were diverted to the coastal city of Mombasa.

Flames and a massive cloud of dark smoke could be seen from the center of Kenya’s capital city, as part of the airport—the region’s largest—became a blackened shell. Emergency vehicles were immediately dispatched only to be caught in rush hour traffic on the main road to the airport. Fire trucks were faced with low water supplies at the site of the blaze.

Domestic flights resumed after the fire was under control, but international flights remain suspended until Thursday, when limited air travel is expected to resume.

“There has been serious disruption of the aviation operations at the airport,” reported Manoah Esipisu, Kenya's secretary of communication. “Contingency measures have been put in place to stabilize the situation and to return the airport to normal operations.”

The cause of the blaze is still being investigated, but officials have not ruled out terrorism. No casualties have been reported.

Earlier this week, malfunctions with a fuel jet pump at Jomo Kenyatta International Airport caused more flights to be diverted to other airports in the region.

The airport, which sees some 16,000 passengers a day, is key to East Africa’s tourism business. An estimated 1.8 million visitors arrive in Nairobi annually, many en route to big game reserves for safaris. Such popular spots as Nairobi National Park (home to large herds of zebra, cheetah, and hippos), the Sheldrick Elephant Orphanage, and the Giraffe Center are not far from Nairobi city limits.

Travelers with plans to travel to, or through, Nairobi should contact their airlines immediately.

Adrien Glover is deputy digital editor at Travel + Leisure.