A United Airlines passenger jet struck a coyote on the runway during takeoff in Chicago, forcing the flight to return to O’Hare International Airport to have the landing gear examined.

None of the 167 passengers or six crew members aboard the Boeing 737 MAX 9 were injured in the incident on Sunday, which forced the Phoenix-bound United Flight 1727 to make a swift return, the airline said Thursday in an email.

“We arranged for another plane to take our customers to their destination later that afternoon,” the airline said.

The Federal Aviation Administration is investigating, saying Thursday that the crew initially reported that the plane had struck a bird.

Collisions between aircraft and wildlife are a growing concern for aviation safety, according to the FAA.

The FAA said that between 1988 and 2023 wildlife strikes with civilian and military aircraft killed more than 491 people and destroyed more than 350 aircraft across the globe. In the United States, wildlife strikes with civilian and military aircraft killed 76 people and destroyed 126 aircraft between 1988-2023.

Most collisions involve birds, but between 1990-2023 there were 882 reported civilian aircraft strikes with coyotes and 1,301 with white-tailed deer in the U.S., according to the FAA.

Coyotes are finding a niche in many urban and suburban communities across the U.S. On Monday, a coyote was found inside a Chicago grocery store before it was captured and removed by authorities.

In 2020, two people — included a 6-year-old boy — were reportedly attacked by a coyote or coyotes in the city’s downtown area. A coyote sighting also prompted the lockdown of two schools in the city’s Lincoln Park neighborhood.

Coyotes are particularly active January through March, the animals’ mating season, officials have said.