The suspicious person who caused an unscheduled two-hour stop for a Metra train this morning and a search of its passengers was a U.S. Secret Service agent.

Metra spokeswoman Judy Pardonnet said the incident began when a plainclothes Secret Service agent asked a Naperville ticket agent whether there were metal detectors aboard the BNSF Line train and indicated he was carrying a gun.

"He did not identify himself as any type of law-enforcement officer. That concerned the ticket agent," Pardonnet said.

But Kristina Schmidt of the Secret Service office in Chicago said a preliminary review showed the agent had acted properly and identified himself to the ticketing staff.

Schmidt said the agent noticed the Metra employees eyes go to his waist and look at his service weapon as he was taking out his wallet to buy a ticket.

"He verbally identified himself as law enforcement and said that he was armed," Schmidt said. "That was pretty much the extent of their conversation."

Assuming all was fine, the agent boarded the train, she said.

It was a few minutes later that police boarded the train. The agent again identified himself, Schmidt said, not realizing his interaction with the Metra employee had led to the train being stopped.

The express train departed the downtown Naperville station at 8 a.m., then made an unscheduled stop in Lisle. Lisle police boarded the train and searched 2 1/2 cars before finding the man.

Metra trains began running again at 9:40 a.m., Pardonnet said.

Pardonnet said the Secret Service agent had never taken the train before.

"Apparently he was unfamiliar with the system," she said. "He was riding it today because it was snowing."

Pardonnet said the ticket agent acted properly.
Sergeant Ron Wilke of the Lisle Police Department said no charges would be filed, and he declined to identify the agent.

"It sounds like it was a miscommunication," Wilke said. "It probably should've been handled better from their end."

The incident stopped train service in the western suburbs this morning as police armed with semiautomatic rifles evacuated and searched train passengers at the Lisle station.

More than 1 1/2 hours later, passengers were allowed to reboard the No. 1252 express train. Service then resumed on the line.

The ticket agent had told police a suspicious man was asking "unusual questions that were security-based" at the Naperville Metra station, Naperville Police Cmdr. Dave Hoffman had said. Officers were unsure if the man got on the train so authorities decided to stop it near Lisle to search for him, he said.

Several hundred passengers from the emptied cars milled about in the Lisle station this morning after authorities cleared several of the train's cars. About 9:45 a.m., passengers began rushing to get back onto the train after they were told the train was safe.