LOWELL, Ind. (AP): Investigators are looking at a large propane storage tank as the possible source of a deadly house explosion in rural northwestern Indiana.

Lake County Sheriff John Buncich said Tuesday that state and local fire investigators are looking for records on the propane tank at the house near Lowell. The explosion Monday night killed 43-year-old neighbor Victor Strain.

Patty McLane of Avon says Strain helped watch her father's house after he recently moved into a nursing home. McLane says the explosion happened as her brother was on the phone with Strain, who was checking on something suspicious.

Buncich says Strain apparently thought he saw something at the back of the home and the blast happened when he opened the door.