St. Louis County police say an 11-year-old boy fatally shot a 16-year-old intruder during a home invasion, but some neighbours take issue with that account.

Officers responded Thursday afternoon to a report of a shooting at a north St. Louis County home, Police Sgt. Brian Schellman told The Associated Press.

Police believe two suspects had tried to break into the home twice earlier in the day. On the third try, they were able to enter through the front door, Schellman said.

Soon after the 16-year-old entered, the 11-year-old fired a single shot that struck him in the head, Schellman said. The body of Lamonte Streeter, who lived just a couple of blocks away, was found in the front foyer.

Schellman said the shot may have scared away the second suspect, a 22-year-old suspect who remained jailed Friday after being arrested on suspicion of burglary. Prosecutors were reviewing the case to determine if charges should be filed.

Some neighbours told the St. Louis Post-Dispatch that they witnessed the shooting and there was no break-in.

Donna Jackson told the newspaper that she saw the 11-year-old shoot the 16-year-old at point-blank range as they talked near front door.

"It was not a break-in," Jackson, 45, said. "He shot him in the head."

Jazmyne Clark, 18, who lives two doors down from the shooting, said the 11-year-old was on the front porch when he told the 16-year-old to approach him. When the 16-year-old reached the front door, the younger boy shot him, Clark said.

Schellman said evidence indicated the shooting happened inside.

The 11-year-old and his 4-year-old sister were not hurt. Their mother wasn't home during the incident but is co-operating with an investigation, Schellman said.