ST. LOUIS — Police found three dead at a north city house on Friday morning, and killed a man they said was a suspect in their shootings.

The standoff started early Friday.

The department was alerted to the shooting by its ShotSpotter system, which detects and locates gunfire across the city, police said.

Officers arrived at the house just after 4 a.m. in the 5100 block of Wells Avenue, near Sherman Park and Kingshighway.

They found a man shot on the front porch, police said. He died there. 

Police then sought a search warrant. Officers surrounded the house as they waited.

At around 7 a.m., a man inside the house came out, talked to cops, and went back inside, police said.

Moments later, he came out of the house again, this time armed with a rifle, police said.

He fired at officers, police said, and one St. Louis police officer and one ATF agent fired back at the man.

He then went back inside the house.

Before 9 a.m., SWAT officers entered the house.

Inside, they found the suspect dead near the front door, a woman dead in the living room and man dead in the basement, police said.

The police officer who shot at the man is 28 with three years of service.

Authorities said no officers appeared to be hurt.