PHILADELPHIA (AP) -- An assembly line worker charged with vandalizing a military helicopter at a Boeing plant was upset about a job transfer and cut a bundle of about 70 electrical wires during his last shift on the Chinook line, federal investigators said Tuesday.

Matthew Kevin Montgomery, 33, of Trevose, had worked at the plant near Philadelphia for about 18 months before his arrest Monday, nine days after the H-47 Chinook aircraft was disabled.

Authorities say he is not currently a suspect in a separate act of vandalism on another helicopter at the plant.

Montgomery continued to work at the plant, where he made $19.10 an hour working the second shift, until meeting with federal investigators Monday, when he allegedly confessed.

U.S. Magistrate Judge Henry Perkin agreed at a hearing Tuesday to release Montgomery on $25,000 bail and ordered him to live with his parents in Southampton, undergo a mental health exam, and have no contact with Boeing or its employees.

''He's very concerned and very remorseful,'' said public defender Mara Meehan. ''He's been pretty upset, which is one reason why concerns have been raised about mental health.''

Montgomery refused to answer questions from an Associated Press reporter after the hearing.

He admitted cutting the wires on the morning of May 10, according to an arrest affidavit. The helicopter would not have been able to fly with the cut wires, investigators said.

The production line was shut down early last week after the vandalism was discovered by workers inside the Ridley Park plant. Federal officials handed out fliers to workers, offering a $5,000 reward for information.

''I don't think there's anybody who cares more about resolving this than the people whose jobs are on the line,'' U.S. Attorney Patrick Meehan said at a news conference Tuesday.
U.S. Rep. Joe Sestak has said that a suspicious washer was found in the second helicopter.

''The focus of the investigation continues to be on one or more Boeing employees,'' federal investigators said in a statement. ''Montgomery is not currently a suspect in the second investigation.''

The Chinook is the Army's workhorse aircraft, used to move troops and supplies. Boeing is producing new Chinooks for the Army, as well as updating older models.

A union official said he believes the vandalism was committed by someone with personal problems, not over any contract issues at the plant.

''A lot of our members are relieved, saying this type of person does not belong in this facility,'' said John DeFrancisco, the president of United Auto Workers 1069. ''They can go back to work and not have to look over their shoulders or feel there's anybody in there doing damage.''