Prosecutors have charged a fourth person in an Indianapolis house explosion that killed two people and damaged dozens of homes.

Two counts of murder and dozens of arson charges were filed Thursday against 44-year-old Gary Thompson in the November 2012 natural gas blast that killed a couple living next door.

Thompson is scheduled to appear in court Friday for his initial hearing on the charges.

Court documents say Thompson was involved with tampering with the natural gas flow in the home of Monserrate Shirley and setting a timing device to ignite the gas.

Shirley is also charged in the blast, along with her former boyfriend, Mark Leonard, and his brother, Bob Leonard.

A judge is considering a plea deal in which Shirley would plead guilty to two counts of conspiracy.