A man was stabbed Thursday evening at a Gaithersburg area shopping center, possibly during a robbery attempt, Montgomery County police said.

It was not clear whether the man, who police said is 50 years old, was a store employee or a shopper. But officials said police are investigating the possibility that the man was assaulted during a robbery.

Authorities were called to the Flower Hill Shopping Center in the 18200 block of Flower Hill Way about 6:30 p.m., said Officer Amy Daum, a Montgomery County police spokeswoman. The man was stabbed in the upper body, she said in a statement, but it was not clear how seriously he was injured.

According to the statement, an unspecified number of suspects were believed to be involved in the assault. They were still at large as of about 9 p.m. Thursday.

This report has been updated.