Ten people were injured and nearly 1,000 were evacuated after an escalator began emitting smoke at Kennedy International Airport on Wednesday morning, airport officials said.

The escalator, in Concourse C of Terminal 8, started smoking around 7:15 a.m., according to the Port Authority of New York and New Jersey, which operates the airport. The Fire Department and Port Authority police officers responded, and about 990 travelers were taken by bus to other areas of the terminal, according to the Port Authority. Four of the injured people were hospitalized, officials said; their injuries were not life-threatening.

Terminal operations resumed later in the morning. The cause of the smoke was under investigation, officials said.

Departures from the airport were delayed by up to an hour and 30 minutes because of the weather on Wednesday evening, according to FlightAware, a company that tracks flight information. It was unclear whether any of the delays were related to the earlier smoke conditions.

Eleven U.S. and international airlines, including American Airlines, British Airways and Japan Airways, use Terminal 8.

Shayla Colon contributed reporting.