An American Airlines flight attendant was found dead in a Philadelphia airport hotel room with a sock in her mouth, two days after she was supposed to check out.

The 66-year-old woman from Las Vegas was discovered unresponsive by cleaning staff at the Philadelphia Airport Marriott on Monday evening and medics pronounced her dead around 10:40 p.m.

There were no signs of forced entry or a struggle and no weapons were found inside the room, 6ABC reported, citing police sources.

Sealed prescription bottles were found inside the room, and investigators said she was on “several medications.”

A cause of death has not been determined, but she “suffered a sudden death,” Chief Inspector Scott Small told NBC10.

The woman’s identity has not been made public as autopsy results haven’t been released as of early Wednesday.

Small told the outlet the woman’s death is considered “suspicious” and is being investigated by the police department’s Homicide Detectives Division.

The Philadelphia police did not immediately respond to The Post’s request for comment.

In June, an American Airlines flight attendant died when she collapsed mid-flight on an overseas trip back to the US.

Carol Wright, who worked with the airline for 38 years, unexpectedly collapsed on a flight from Venice to Philadelphia aboard a Boeing 787-8 Dreamliner, according to the Mirror.

The plane diverted to Dublin, Ireland, while the crew made “valiant efforts” to save Wright, but she was pronounced dead at a local hospital.