US abducted girl found dead

US authorities have found the body of a five-year-old Minnesota girl, just hours after they had issued an Amber Alert saying she had been abducted by a family friend.

The body of Alayna Jeanne Ertl was found in Cass County, about 320km north of Minneapolis.

The suspect in her disappearance, family friend Zachary Anderson, 26, has been arrested and a vehicle found, police said.

Ertl's body was found shortly after 5pm in the rural town of Motley, Meeker County Sheriff Brian Cruze told the Star Tribune.

She was dead when police arrived on the scene, he said.

"That's part of our follow up right now, to figure out - why there?" Cruze said.

Police said Anderson was staying overnight at the girl's home in Watkins, west of Minneapolis.

The girl's mother discovered them gone at 8am.