Marion County Prosecutor Terry Curry announced Friday that three people have been arrested in connection with a home explosion in an Indianapolis suburb that killed two people last month and damaged dozens of homes.

Monserrate Shirley, her boyfriend Mark Leonard, and his brother Bob Leonard Jr. have been charged in connection with the Nov. 10 explosion in Richmond Hill. The explosion at Shirley’s residence ignited a fire at the home of next-door neighbors John and Jennifer Longworth, who died as a result.

The three, who were arrested Friday morning, face two counts of felony murder, one count of Class A felony conspiracy to commit arson, 12 counts of Class A felony arson, and 33 counts of Class B felony arson.

Mark Leonard and Shirley are also charged with an additional count of Class B felony conspiracy to commit arson. Investigators say the weekend before the explosion, Mark Leonard and Shirley also boarded their cat, had Shirley’s daughter stay with a babysitter at another home, and went to a casino. It’s alleged that the two attempted to set a fire that weekend, but for some reason it failed. They went through the same steps the weekend of the explosion.

The explosion also caused injuries to 12 people who lived in the neighborhood. At a press conference Friday, investigators said they discovered the microwave in the home of Shirley appears to have exploded from the inside out and that Mark Leonard recently changed the home’s thermostat from a digital one to a slide switch one, which could cause a spark. They also believe someone removed the step-down regulator to the manifold to the gas lines coming into the house, opened or removed the fireplace valve to allow for the flow of gas into the residence, and/or set a timing device to cause the ignition of the gas.

The probable cause affidavit notes that Shirley filed for Chapter 13 bankruptcy this year but stopped making payments. There are two mortgages on the home and she owes $63,000 in unsecured credit card debt. Shirley recently increased the coverage limit on personal property on her homeowners’ insurance.

Curry emphasized at the news conference that these are just charges and the suspects are due their time before a court of law.