Prosecutors in Indiana say a fourth suspect has been arrested in relation to a 2012 explosion that ripped through an Indianapolis neighborhood, leveling homes and killing two people.
Gary Lee Thompson, 44, was arrested Wednesday and is being held on suspicion of two counts of murder and a felony charge of arson, according to records from the Marion County Sheriff's Office.
He is expected to be charged Thursday.
Prosecutors did not say how Thompson was connected to the blast or to three other defendants who, prosecutors say, intentionally blew up a house as part of a plot to collect on insurance money.
Monserrate Shirley, who owned the house, her boyfriend Mark Leonard and his older brother Bob Leonard each face two counts of murder, a count of conspiracy to commit arson and multiple counts of arson.
Shirley, 49, agreed last week to plead guilty to two felony counts of conspiracy to commit arson, according to Peg McLeish, a spokeswoman for the Marion County prosecutor's office. In exchange, McLeish said, Shirley agreed to cooperate with investigators and provide information in the case against the Leonard brothers and "unnamed yet uncharged individuals."
Prosecutors say the trio intentionally leaked natural gas into Shirley's house and then used a programmable microwave to trigger the Nov. 10, 2012, blast. The explosion killed Jennifer Longworth, 36, and her husband, John "Dion" Longworth, 34, who lived next door. It also destroyed five homes and damaged dozens of others so badly that officials ordered their demolition.
Mark Leonard, 45, also faces a murder-conspiracy charge. Prosecutors said that while in jail, he tried to hire a hit man to kill a key witness against him in the case.
McLeish said prosecutors expected the cases would be among the most challenging the agency has faced, with more than 200 witnesses lined up for each man's trial.