Indianapolis officials have opened a homicide investigation into the massive house explosion Nov. 10 that killed a married couple and ruined more than 30 homes.
The announcement at a Monday night news conference came hours after the burial of Dion and Jennifer Longworth, who had lived in a neighboring house.
Officials offered few details, but said they had executed warrants and spoken with witnesses.
Marion County Prosecutor Terry Curry said a "parallel investigation" into the explosion's cause now had them searching for a white van spotted in the area around the time of the blast.
The explosion had been felt for miles and forced residents to evacuate the 126-house subdivision. The blast damaged most of those homes, blowing doors open and some roofs away, and rendered more than 30 houses uninhabitable. Authorities blocked off the scene and found the Longworths' bodies shortly after.