CLEVELAND -- A lockdown and reports of a gunman at a NASA research facility on Friday resulted from a false alarm, a misunderstood message sent during a test of the facility's automated emergency notification system, authorities said.
"There was not a shooting," said Lori Rachul, a NASA Glenn Research Center spokeswoman, adding that an employee thought there was.
A person who received a notification during the test did not realize it was a test, explained Lt. Don Michalosky of the Cuyahoga County Sheriff's office. He said he did not know the specific contents of the message but that it led to a story being spread among employees that there was a gunman in the building.
"The story gets passed along and gains momentum," Michalosky said. "I believe they were contacting their loved ones."
Officials planned to provide more details about the incident at an afternoon news conference, Rachul said.
Loudspeakers announced "All clear" and "The emergency is over" shortly before 11 a.m. at the sprawling complex next to Cleveland's airport. NASA Glenn was placed under what was described as a "complete lockdown" earlier in the morning; a spokeswoman had declined to confirm reports that a gunman was being sought.
Dennis Pehotsky, a retired safety officer at the center, said false alarms are common at NASA Glenn.
"Crews are working out there all the time and it never ends, false alarms," he said. "They cut into wires and everything else and they set off alarms. This kind of thing happens frequently."
The emergency notification problem represented a second glitch Friday for NASA, which also delayed the space shuttle Discovery's final voyage, possibly until the end of the month, because of a potentially dangerous hydrogen gas leak discovered during fueling.
The NASA Glenn complex, alongside Interstate 480 and next to Cleveland Hopkins International Airport, has tight security, with visitors required to sign in, get a pass and be escorted on the grounds. Security was beefed up after the Sept. 11, 2001, terrorist attacks.
The center has weathered several years of staff cuts and is facing uncertainty over potential cuts in space programs.
NASA Glenn has more than 3,400 employees and contract workers and developed some key components of a rocket for NASA's now-canceled $100 billion return-to-the moon program.
The center is named after Ohio resident John Glenn, who piloted the the United State's first manned orbital mission in 1962.
Associated Press writers Thomas J. Sheeran in Cleveland and John Seewer in Toledo contributed to this report.