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By Associated Press

A jury convicted an Indianapolis man of murder, arson and insurance fraud Tuesday for his role in a house explosion that decimated a subdivision nearly three years ago, killing a couple living in the neighborhood.

The jury found 46-year-old Mark Leonard guilty of all counts against him, including murder and felony murder. Prosecutors alleged Leonard was the mastermind behind the explosion, plotting with his then-live-in girlfriend Monserrate Shirley and his half-brother Bob Leonard to blow up the home for $300,000 in insurance.

Shirley accepted a plea deal and testified against her former boyfriend. Bob Leonard and two others are awaiting trial.

During opening statements in the monthlong trial, defense attorney Diane Black described the explosion that damaged or destroyed 80 homes as "a stupid and selfish insurance fraud that went horribly wrong."

The coroner ruled Dion Longworth died of inhaling hot gases and soot and had burns over 90 percent of his body. Jennifer Longworth died of blast injuries that caused almost instant death.

Prosecutors told jurors they don't believe Leonard intended to kill the Longworths but should have known that by using a combination of natural gas and gasoline that he should have known the possibility of someone dying.

In this file photo taken on Wednesday, July 10, 2013, Mark Leonard walks to a pre-trial hearing in Indianapolis.Darron Cummings / AP

Marion County Deputy Prosecutor Denise Robinson said Leonard and the others made sure they, Shirley's daughter Brooke and her cat Snowball were nowhere near the house at the time of the explosion "because of the probability of what would happen" after removing safety valves, allowing natural gas to pour into the house.

Testimony included neighbors describing being awakened by what some described as the loudest noise they ever heard, with some believing the explosion occurring in their own homes. Others testified they thought a plane had crashed into the neighborhood.

Leonard was charged with two counts of murder, two counts of felony murder, 12 counts of arson involving bodily injury, 34 counts of arson with no bodily injury, two counts of conspiracy to commit arson and one count of conspiracy to commit insurance fraud.

The defense laid the groundwork for a possible appeal by making several requests for mistrials, including one over alleged prosecutorial misconduct that led St. Joseph County Superior Court Judge John Marnocha to delay testimony for a day.