A female American Airlines flight attendant has been found dead with a sock in her mouth in a hotel room near Philadelphia’s Airport, according to ABC News' Philadelphia station WPVI.

Cleaning staffers discovered the unnamed 66-year-old victim late Monday evening at approximately 10:45 p.m. at the Philadelphia Airport Marriott directly adjacent to Philadelphia International Airport.

Investigators told ABC News’ Philadelphia station WPVI that the woman worked for American Airlines and was supposed to have checked out of her room two days earlier.

It is unclear why her body went undiscovered during that period, but authorities were immediately notified after cleaning staff made the discovery.

“It’s very strange,” Tracee Quinn of Ferris Hills, Pennsylvania, told WPVI in an interview. “And it seems like [there are] a lot of unanswered questions. But it is very sad.”

Several sealed bottles of prescription drugs were found in the room, according to WPVI, but police also reported that there were no signs of forced entry, struggle or any weapons recovered during their investigation.

An autopsy is now pending to determine the cause of the flight attendant’s death.

Police said the case is suspicious and that the Homicide Detectives Division is now investigating, according to WPVI.