Two men were found dead in the landing gear compartment of a JetBlue plane in Florida during routine post-flight inspections on Monday, officials said.

Their identities and the circumstances of their death were unclear and under investigation, Carey Codd, a spokesperson with the Broward Sheriff’s Office, said at a news conference Tuesday morning.

Codd said paramedics declared the two men dead after deputies with the sheriff’s office responded to a call at Fort Lauderdale-Hollywood International Airport about 11:30 p.m. Monday.

Codd said the Broward County Medical Examiner’s Office will perform autopsies to determine the causes of death of both men.

In a statement, JetBlue said officials were investigating how they accessed the aircraft.