Indianapolis law enforcement believe a home explosion that killed two people and damaged 86 houses in the Richmond Hill subdivision was not an accident, reports the Indianapolis Star. "We’re turning this into a criminal homicide investigation,” said Gary Coons, chief of the Indianapolis Department of Public Safety’s Homeland Security division.

Marion County Prosecutor Terry Curry said the continuing investigation includes witness interviews and search warrants and that authorities are seeking information about a white van seen in the area. Officials offered two rewards, one for $1,000 from Crime Stoppers of Central Indiana and another for $10,000 from the federal Bureau of Alcohol, Tobacco, Firearms, and Explosives, for information leading to the arrest and conviction of the person or persons responsible for the blast. For about three weeks, one local man who does regular patrols of the neighborhood saw a white van in front of the house that is considered the epicenter of the blast. He said it was a windowless work van, about 15 years old. The blast is believed to have originated at the home of a nurse whose boyfriend has a long criminal record.