A strike by workers at Kenya’s main airport disrupted flights on Monday, leaving some passengers at Jomo Kenyatta International Airport in Nairobi as airlines adjusted schedules, the Associated Press reported. Kenya Airways said passengers should verify their flight status before proceeding to the airport. The airline also pointed to delays connected to air traffic control operations, saying flight schedules would have to change.

The Kenyatta airport is a major hub for regional and international travel, and Monday’s disruptions reflected how quickly labor actions can translate into schedule changes for airlines and knock-on effects for travelers. AP reported that thousands of passengers were seen sitting outside the airport as departures and arrivals were affected.

In its advisory, Kenya Airways urged customers not to go to the airport without a confirmed flight status. The airline said air traffic control operation delays were affecting departures and arrivals, and that adjusted flight schedules would follow. Some families told AP that relatives were stuck inside terminals.

AP reported that one passenger who declined to provide his name and details said he had been waiting at the airport for six hours in hopes of boarding a plane. The report also included comments from Canadian passenger Trent Bryski, who said no information had been provided and that his visa had expired. Bryski said he was not supposed to remain in the airport because his visa indicated he had left, and that authorities had provided a special letter, but he said he did not know when he would be able to leave again.

Kenya’s Airports Authority said it took contingency measures to minimize disruptions while it worked to resolve the ongoing strike. The authority stressed that it remained open to constructive dialogue. Workers issued the strike notice after authorities failed to implement part of an agreement with the union, an agreement that sought improved labor conditions and increased pay and benefits.