“If people see him, they should not approach Card or make contact with him in any way,” Maine Public Safety Commissioner Mike Sauschuck told reporters at a news conference. 

At least 22 people have been killed, a Lewiston police source told NBC News. Fifty to 60 people were wounded at several locations, according to law enforcement officials.

Officials urged residents of Lewiston and neighboring Auburn to shelter in place, and a local medical center said it was rushing to respond to a “mass casualty event.”

Authorities did not disclose any information about Card. The University of Maine confirmed that he studied engineering there between 2001 and 2004.

Maine court records show that a man named Robert Card who was born on the same date as the person of interest identified by police was previously charged for speeding in 2001 and 2002. No other criminal records were listed in the state’s electronic court records system or in several other public records databases.

A bulletin put out by the Maine Information and Analysis Center, a database for law enforcement officials, said that Card was a trained firearms instructor and believed to be in the Army Reserve.

It added that law enforcement said Card “recently reported mental health issues to include hearing voices and threats to shoot up the National Guard Base in Saco, ME.”

The bulletin said Card was reported to have been committed to a mental health facility for two weeks this summer and then released. NBC News has not been able to independently verify the bulletin’s statements about Card’s history.

This is a breaking news story. Please refresh for updates.