Employees of NASA's Jet Propulsion Laboratory near Los Angeles were advised to stay indoors on Tuesday after a 200-pound bear was spotted roaming the campus.

The lab arranged escorts for workers at the north side of the facility, which manages many of NASA's planetary space missions, JPL spokeswoman Veronica McGregor said, after the bear was seen there at about 4 a.m. local time.

By 9 a.m. the animal had apparently wandered back into the hills surrounding JPL, which is nestled in the foothills above Pasadena next to the Angeles National Forest, McGregor said.

They did estimate the bear's size at about 200 pounds and it was spotted in the early predawn hours so that's why we were able to put out the notification, she said.

McGregor said the bear was believed to be the second in the last decade to ramble onto the lab property, which also has had visits from deer and at least one mountain lion.

The Jet Propulsion Laboratory is a federally funded research and development center and NASA facility that in recent years has managed the Mars Exploration Rovers, Mars Reconnaissance Orbiter and Cassini-Huygens probe to Saturn.