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INDIANAPOLIS, Ind. (Jan. 30, 2015)– Marion County Prosecutor Terry Curry said the fourth suspect in the 2012 Richmond Hill case denied playing an active role in the fatal explosion but admitted trying unsuccessfully to blow up the house twice in the weeks before.

Gary Thompson, 44, faces two counts of murder, a count of conspiracy to commit arson and 46 counts of arson. He’s due to appear in Criminal Court 3 for his initial hearing at 9 a.m. Friday.

Thompson had known lead suspect Mark Leonard for several years while working at the now-abandoned Holidome at Thompson Road and South Street on Indianapolis’ south side.

“He acknowledges in October of 2012 that Mark Leonard offered him $5,000 to burn Miss Shirley’s house and was given six cans of gasoline for the purpose of doing so,” said Curry, quoting from the Probable Cause Affidavit that charged Thompson with two counts of murder and 47 counts of arson related to the blast at the home of Monserrate Shirley. “Miss Shirley’s statement is that they were told by Mr. Thompson that he was stopped by a police officer on the way and became scared and therefore did not go through with the plan to burn the house.”

Shirley gave a statement to investigators on Jan. 9 of this year, several days before agreeing to plead guilty to arson and to testify against her co-conspirators, including her boyfriend Leonard, to avoid a sentence of Life Without Parole if convicted of murder.

Neighbors Dion and Jennifer Longworth died in the insurance fraud explosion that leveled Shirley’s house and caused $4 million in damages to the surrounding community.

“The following week, according to Miss Shirley’s statement, she observed Mr. Thompson and Mark Leonard stuffing cardboard up the fireplace to block the chimney, but, again on the second weekend, the attempt failed,” said Curry who further alleged Thompson attempted to replace a thermostat in the home to more easily set off an explosion.

“It is alleged in there that he assisted in the removing and replacing the thermostat and then, in turn, taking it back off again.”

A witness told police he saw men matching the descriptions of Thompson and Bob Leonard, Jr., Mark Leonard’s brother, at Shirley’s house hours before the explosion on Nov. 10, 2012.

Based on Shirley’s statement, investigators questioned Thompson on Jan. 19 and again on Jan. 23, and while he denied being present on the day of the fatal blast, he admitted conceiving of the ignition source that set off the explosion.

“Gary Thompson advised there was discussion that the microwave oven could also be programmed to start with metal in the microwave which would spark and become an ignition source,” according to court documents.

Investigators believe the conspirators placed a propane tank inside the microwave oven and set the timer for approximately 11 p.m.

Curry said that while investigators interviewed Thompson early on as an acquaintance of Leonard’s, they did not focus on his alleged role as a co-conspirator until Shirley made her statement.

“In his statement, Mr. Thompson denies to investigators any involvement in the explosion that occurred on November 10,” said Curry.

The Thompson charging document also contains previously unknown details about Shirley’s account of the explosion planning and aftermath.

Shirley told investigators that Leonard was growing desperate over his gambling losses and goaded her into the insurance fraud scheme which was intended to pay the couple $300,000.

“Does she know what you are going to do?” Shirley quotes Bob Leonard, Jr., as asking his brother.

“Oh yes she knows,” answered Mark Leonard.

Shirley told Bob Leonard, Jr., that she had offered her boyfriend, “her 401K and offered him all her money and Mark Leonard said that she does not have enough.”

Leonard owned two wrecked vehicles, a motorcycle and a Cadillac, and wanted at least $20,000 for each vehicle destroyed in a fire.

A friend warned Shirley that, “You’re crazy, Bob Leonard is crazy, they are going to blow up the whole neighborhood.” The single mother of an adolescent girl tried to back out of the plot but “Mark Leonard was angry and broke the flat screen TV in the bedroom in a fit of rage.”

Shirley said Bob Leonard, Jr., was to be paid $10,000 for setting the explosion and said, “Mark, everything’s going to be fine how it is, it’s gonna happen, the fire is gonna happen.”

Mark Leonard is quoted by Shirley as saying that when she would file her insurance claim after the fire, “They won’t suspect anything.”

When the home exploded in a blast that rocked the south side of Indianapolis, Mark Leonard and Shirley were at a southeast Indiana casino. They raced home to find the plot exceeded their wildest expectations.

“Shirley told them she was upset about what happened and Bob said to her, ‘You’re in it,'” reads the probable cause affidavit. When Shirley said she was upset about the deaths, she quoted Bob as saying, “I don’t care who died, you’re in this with us.”

Mark Leonard received $500 from his girlfriend to pay his brother after the explosion. His trial is set to begin in South Bend on June 4.

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