Massachusetts State Police said Friday that they took a gun off a JetBlue pilot at Logan International Airport after he allegedly told an acquaintance he might harm himself.

The pilot was not charged with illegal possession of a firearm, suggesting he might be a member of the Federal Flight Deck Officer program. The post-9/11 program screens, trains, arms and deputizes pilots as a last line of aircraft security. There are reportedly 10,000 pilots carrying handguns under the program.

The conflict occurred Thursday, and the pilot was taken to Massachusetts General Hospital for evaluation. The airline refused to identify him and issued a statement saying he was removed from duty "for health-related reasons."

JetBlue also said no passengers were harmed, nor was any flight in jeopardy.

State Police spokesman David Procopio told The Associated Press a federal air marshal alerted state police about 1:45 p.m., after the acquaintance reported a communication "that suggested a possible inclination by that person to harm himself."

Procopio said three troopers, quickly backed up by four more, confronted the pilot at a crew lounge. The pilot volunteered to undergo a medical evaluation and was taken away by ambulance.

"The subject was in possession of a firearm, which has been seized. The investigation is ongoing," said Procopio.

Asked whether the pilot was a member of the Flight Deck Officer program, Procopio said: "He was not charged with firearm possession."

The Transportation Security Administration refused to confirm whether the pilot was a member of the program, citing security concerns.

"We have an investigation ongoing, and when that is finished, we will release more details," said TSA spokesman Nelson Minerly.