A Cold Spring police officer was fatally shot late Thursday when he was trying to do a routine welfare check at an apartment near a Main Street bar, Stearns County authorities said Friday morning.

A suspect was arrested after the shooting and remains in custody, Sgt. Ken Friday of the Stearns County Sheriff's Office said.

Investigators didn't release the name of the dead officer or the suspect.

However, the Stearns County jail log shows a Ryan Michael Larson was booked into the jail early Friday on suspicion of murder. He is the only person brought to the jail in the last 24 hours on a murder charge.

Shortly after 11 p.m. Thursday, helicopters circled over the town just west of St. Cloud, as officers cordoned off much of the downtown and combed the area for a suspect near a dam on the Sauk River.

Emergency response teams from St. Cloud, Stearns County and the Minnesota State Patrol joined the effort and by a few minutes after midnight police emergency radio channels confirmed that one man was in custody.

Residents who couldn't get past police blockades to return home were directed to the city fire station to await an all clear or help in finding alternate lodging. Mayor Doug Schmitz was called downtown by 11:30 p.m. but said he couldn't release any details about the shooting or the victim until the city held a news conference Friday morning.

The last Stearns County officer killed in the line of duty was St. Joseph officer Brian Klinefelter, who was shot in 1996 while attempting to arrest three robbery suspects.