Deadly blast still a mystery

INDIANAPOLIS

- The search for what caused a massive, deadly explosion that rocked a quiet neighborhood turned to natural gas Monday, with officials checking gas lines.

The National Transportation Safety Board sent investigators to check gas-main and other lines serving the neighborhood where two people were killed and seven injured in the weekend blast. Local gas supplier Citizens Energy said it also was checking gas lines and a meter at the home that exploded.

But officials cautioned that it was too soon to rule out other causes, saying only that they do not believe a meth lab was to blame for the explosion that obliterated two homes and severely damaged dozens of others.

"It's too early to speculate that this might have been caused by a gas leak," Citizens Energy spokeswoman Sarah Holsapple said at an afternoon news briefing.

Investigators said it could be some time before they determine a cause for the blast, which sparked a massive fire, blew out windows, collapsed ceilings and shook homes up to three miles away.

Public Safety Director Troy Riggs said investigators will treat the area as a crime scene until they rule out foul play.

The blast forced about 200 people out of their homes in the once-tidy neighborhood of one- and two-story single-family houses. Some residents have been allowed to reoccupy their homes, and others have been escorted in to retrieve valuables and other belongings.

Adam Collins, the city's deputy code-enforcement director, said 29 homes remained uninhabitable Monday.

Mark Karnes, whose house is four doors down from the blast site and which suffered severe structural damage, hoped to retrieve clothes and look for his cat. But he also questioned the wisdom of going back inside the house, given the extent of the damage.