Investigators say a silver knife was found near the body of a 10-year-old boy found in the Mississippi River in Minnesota, three weeks after he was reported missing.

A search warrant released Wednesday says officials searched the home of Barway Collin's family two days after his duct-tape-bound body was discovered April 11 by Boy Scout volunteers.

The warrant says authorities were looking for knives similar to a silver knife with a patterned handle found near Barway's body, as well as pieces of duct tape and other items. It says authorities seized six knives, two plastic air conditioner covers with duct tape on them and a towel with plant material on it.

Barway's father, Pierre Collins, is charged with second-degree murder in his death. He's being held on $2 million bail.