BOSTON — A Massachusetts man tried to open an airliner’s emergency door on a cross-country flight from Los Angeles to Boston and then tried to stab a flight attendant in the neck with a broken metal spoon, federal prosecutors alleged Monday.

Francisco Severo Torres, 33, of Leominster, was tackled and restrained with the aid of passengers and arrested Sunday at Boston Logan International Airport when United Airlines Flight 2609 landed, the U.S. attorney’s office in Boston said in a statement.

He was charged with interference and attempted interference with flight crew members and attendants using a dangerous weapon, the statement added.

The man was detained at an initial appearance in federal court on Monday and awaits a hearing scheduled for Thursday. An email seeking comment was left with his federal public defender.

The plane was about 45 minutes from arrival in Boston when the crew received an alarm that a side door on the aircraft was disarmed, prosecutors said.

A flight attendant noticed the door’s locking handle had been moved out of the fully locked position about a quarter of the way toward the unlocked position and that the emergency slide arming lever had been moved to the disarmed position, authorities said. The crew secured the door and slide.

A door in a airplane cannot be opened once in flight due to cabin pressure.

Another flight attendant had noticed that Torres was seen near the door and believed he had tampered with it, authorities said. The crew told the captain that he was a threat and the plane should be landed as soon as possible.

At that point, prosecutors allege, Torres got out of his seat, approached two flight attendants standing in the aisle, and used the spoon to make stabbing motions, hitting a flight attendant three times in the neck area.

Passengers tackled Torres, who was restrained with the assistance of the crew.

According to a charging document, Torres told investigators that he went into the airplane’s bathroom and broke a spoon in half to make a weapon.

When he came out of the bathroom, Torres said he went into the galley, disarmed the door, and tried to open it unsuccessfully with the idea of jumping out of the plane, according to the document.

Investigators said Torres admitted knowing that if he opened the door many people would die.

Torres also said that he was then confronted by flight attendants and, in an attempt to defend himself, stabbed one of the attendants in the neck three or four times, according to investigators. They added Torres said he believed the flight attendant was trying to kill him, so he was trying to kill the attendant first.

Authorities did not say where Torres got the spoon, but TSA rules allow airline passengers to bring metal utensils except knives onto planes.

United Airlines said no one was injured.

“Thanks to the quick action of our crew and customers, one customer was restrained after becoming a security concern on United flight 2609 from Los Angeles to Boston,” the company statement said. “The flight landed safely and was met by law enforcement.”

The airline said it has a zero-tolerance policy for violence and Torres will be banned from flying on United pending an investigation.

One passenger told investigators that Torres had asked where on the safety card it showed where the door handle was located during the flight attendants’ pre-takeoff safety briefing, prosecutors said.

If convicted, he could face life in prison.

The Association of Flight Attendants released a statement saying it was proud of the United flight crew and relieved that no one was seriously injured. It said there was an urgent need for a national list of banned passengers.

“Violence has no place anywhere and certainly not in a closed cabin flying several miles in the air,” Sara Nelson, the group’s president, said in the statement. She added: “When incidents like this happen, it not only risks the safety of the crew involved, it takes away from Flight Attendants’ ability to respond to medical, safety, or security emergencies. Bottom line: it puts everyone at risk and there’s zero tolerance for that.”