Two congressional aides carrying a Halloween costume and a plastic toy gun passed through a security checkpoint in a House office building Thursday, causing a large police search that shut down the House of Representatives.
"I don't think they had any ill intent," U.S. Capitol police Chief Terrence Gainer said of the women, aides to Rep. John Shimkus, R-Ill. "It was just an unusual set of Halloween circumstances that unfolded on us."
But staffers and lawmakers said the incident reveals weaknesses in the Capitol complex's security system.
Gainer said the women had stopped to chat with security personnel after placing a bag on a security station X-ray belt at the entrance to the office building, then went into their building. Moments later, an officer who had been distracted by someone asking a question noticed something that looked like a gun on the video screen and triggered an alarm.
"You could not tell from the X-ray whether it was plastic or real," Gainer said.
Police told occupants of the Cannon House Office Building to remain in their offices while they searched room by room for a possible gunman. They later moved hundreds of people into a large rotunda, where they waited to leave the building.
Police said they were searching for a white man in a suit carrying a .38-caliber gun. A few minutes later, they added a woman in a pink shirt and khaki pants as a second suspect.
"You have to remember the whole thing is unfolding in a matter of seconds," said Gainer, who added that security personnel performed "well within standards."
A sport utility vehicle pulled up, unloading armed and heavily protected police who ran into the building.
"They banged on doors and said everyone needs to leave the building," said Marshall Maher, aide to Rep. Lloyd Doggett, D-Texas. "They hustled the congressman out of here. Everyone grabbed a bunch of folders and files. We were moving operations over to his house."
Shortly after, the women with the costume realized their backpack was the cause of the chaos and Shimkus called the police.
"This was an unfortunate misunderstanding, a result of my staff's efforts to put together a Halloween costume during their lunch hour," Shimkus said in a written apology.
The incident lasted less than two hours, and the House resumed work soon after. Gainer said the unidentified women would not be charged.
"We shut the doors and went about our work until we were told it was clear," said Rep. Jim Davis, the Tampa Democrat whose office is on the fourth floor of Cannon. "It really did not disrupt our workday."
Rep. Carolyn McCarthy, D-N.Y., said an alarm system that is supposed to notify House staff of emergencies did not go off. The media knew of the incident before her office, she said.
After multiple emergency drills, members and office staff should have been told sooner about the potentially dangerous situation, she said.
"This is a system that is supposed to be working, but failed," McCarthy said. "You're going to have some members mad."
_ Information from the Associated Press, Cox News Service and Times staff writer Bill Adair was used in this report.