Sirens and gunfire will rattle through the Century College campus in White Bear Lake Sunday morning, but calling 911 won't be the right response.

Law enforcement officers will be doing an active-shooter response drill, and "we are telling people not to freak out and not to call 911," said Ramsey County Sheriff's office spokesman Randy Gustafson.

Several agencies, including the Washington and Ramsey County's Sheriff's offices, have told neighbors the explosions they may hear at 8 a.m. are just drills.

Commuters should also expect delays on Century Avenue and other nearby roads.

Gustafson said about 60 officers will participate in the training, which is meant to prepare emergency responders in the event of a shooting on campus. "What we want to be able to do is respond and know that our communication systems work between all of the agencies," Gustafson said.

The exercise is expected to wrap up by 1 p.m.

ALEJANDRA MATOS TWITTER: @AMATOS12