A 3-year-old boy was shot to death by a man believed to be the child's father, Albuquerque police said.

The child was shot once in the upper torso with a handgun Monday at a home in southeast Albuquerque, police spokesman John Walsh said. He was pronounced dead at 2:30 p.m. at the University of New Mexico Hospital.

Police were calling it an "unexplained death" as they conducted their investigation.

A 20-year-old man, as well as six other people believed to be witnesses, were questioned, Walsh said.

"We have a strong belief he is the father of the child," Walsh said. "He had direct involvement. He had blood on him."

The department did not release the child's name pending notification of other relatives.