OWASSO, Oklahoma - Neighbors are still shaken after a weekend home explosion severely injured an Owasso couple. Some people spent more than four hours evacuated from their homes.

The Bureau of Alcohol, Tobacco and Firearms continues to investigate the explosions at an Owasso house that injured two people over the weekend. Authorities say a 13-inch mortar shell exploded as a man filled it with gunpowder at his residence in the 11500 block of North 131st East Avenue Saturday morning.

Neighbors heard several loud booms and looked outside to see the man in his front yard, screaming and bleeding from severe injuries to both hands. A woman was also injured in the explosion.

The Falls at Garrett Creek neighborhood was evacuated due to a strong chemical smell, and two Owasso police officers were treated and released for chemical exposure.

"We hope we can get to the bottom of this and get the thing solved," said neighbor Larry Olds.

Carly Gwartney's family was one of six families evacuated after the explosion.

"It's infuriating because if we would have been home, my girls would've seen, because the neighbors here said he came outside and you could tell that he didn't have his hands," she said.

The ATF says its agents collected compounds, residue and debris from the home. Those items are being sent to an ATF crime lab for further analysis.

Police are in the middle of conducting interviews and are waiting to figure out what the man was doing with the shells, before submitting any findings to a prosecutor.

"There were some early indications they were altered as far as cut open and the gun powder taken out," said Owasso Police Deputy Chief, Jason Woodruff.

Neighbors said they've seen police at the home before.

"We knew stuff was happening over there, but nothing like explosives. I'm just glad we weren't home because we play in the yard all the time, we're outside all the time," Gwartney said.

Everyone in the neighborhood just wants things to quiet down and return to normal.

"It's a good neighborhood. Only major problem that I've seen in the six years," Olds said.

Detectives have not interviewed the man; he's still in the hospital.

The Owasso Police Department and the ATF want to stress that the home is safe and it's been cleared by investigators.

Two police officers were checked out by doctors after they inhaled the fumes from the home. They're OK and back at work.