Venango County Deputy Coroner Chris Hile said the trooper -- a 16-year veteran, husband and father of two young children -- was taken to UPMC Northwest Hospital, where he was pronounced dead.

Richey and Trooper Jason Whitman, who was not shot, were called at about 11:34 a.m. to the house for a possible domestic dispute. At about 11:45 a.m., state police said a male voice yelled to the troopers to return to their vehicles. The troopers ordered the man to show himself, at which time, state police said Richey was shot in the torso and Whitman sought cover and called for assistance.

"(The event was) premeditated to the extent that whoever took that shot, they would have the advantage," state police Col. Lenny Bandy said. "Trooper Richey did not have an opportunity to defend himself. He was ambushed."

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More than 100 troopers and officers descended upon the Bouquin Circle section of Oil City, executing a large-scale search of the area in case the shooter had left the house.

"There were roving patrols of troopers driving the perimeter (and) roads just on the off-chance that the individual responsible for this shooting made his way from the residence and somehow entered a nearby roadway," Bandy said.

Troopers went door to door to show a picture of the resident to people who live in the area, saying they considered him armed and dangerous.

Law enforcement sources told Channel 4 Action News, and state police later confirmed, that Pittsburgh police SWAT and Special Emergency Response Team officers dispatched chemical agents into the house at 6:41 p.m. Officers who entered the house found the bodies of a man and woman who died from an apparent murder-suicide. Authorities then lifted a perimeter around the house and ended the search.

State police notified next of kin and later identified the bodies found as Michael J. Smith, 44, and his wife, Nancy Frey-Smith. Police did not immediately release details of the domestic incident that preceded the fatal shooting.

A friend of Smith's wife said that the man "has been on disability" and described him as an outdoorsman who lives off his property by hunting and fishing.

A forensic investigation and an internal investigation into the officers' actions at the scene continues.

Venango Catholic High School was on lockdown after the shooting, along with the Cranberry Area School District and Clarion University's branch campus in Oil City.

Richey worked at the Franklin barracks and is survived by his wife, Carrie, a teacher in the Oil City Area School District, their 9-year-old son, Connor, and their 6-year-old daughter, Catherine.

"The citizens of the commonwealth of Pennsylvania and the men and women of the state police lost a hero today," Bandy said.

"Tpr. Richey sacrificed his life rather than swerve from the path of duty. We will not forget his service or his sacrifice," Commissioner Frank Pawlowski said in a statement on the state police Web site.

The governor has ordered all flags at state buildings be flown at half-staff.

In all, 93 state troopers have died in the line of duty since the Pennsylvania State Police Department's establishment in 1905.

Neighbors Shocked, But Not Surprised By Shooter's Actions

Those who knew Michael Smith told Channel 4 Action News they were shocked by the day's events, but not surprised. They described Michael Smith as very odd and said he at least seemed prone to violence.

Joe Sloss, the closest neighbor to Michael Smith, said he has experienced Smith's violent tendencies.

"I actually tried to help him plow his driveway, and he actually grabbed a shovel like a baseball bat and was kind of threatening me with it," Sloss said.

Sloss read one of the entries from the log, "He was outside yelling at somebody. There was something about money. He owed somebody money and threatened to cut off his head and shoot down his throat. The other guy sped out of the driveway."

Others who knew Michael Smith expressed the same. A man who asked to remain anonymous said of Michael Smith, "He'd get agitated and irritated at times. Kind of moody, he was a bipolar type, you know? I'm kind of in shock about it."

Others getting to return to their homes Wednesday night said they're also in shock that something like this would happen in their neighborhood.

"Losing one of our troops is kind of hard because we're all together in that," said Gary Crawford, a neighbor.

"It's terrible, it's terrible. We just never know do we?" said Debbie Jack, a neighbor.

Michael J Smith

Team 4 Investigates Michael Smith's History Team 4 investigative reporter Jim Parsons says court records show that Smith's wife, Nancy Frey-Smith, obtained a protection-from-abuse order in 1997, as did the woman's mother. At the time, Smith had been charged with resisting arrest, stalking, reckless endangerment, harassment, making repairs or selling an offensive weapon, simple assault and possessing an instrument of crime. No details are available from the PFA petitions that Smith's wife and mother-in-law filed against him. Team 4 was told that those documents were seized from the clerk of courts by the Venango County District Attorney's Office on Wednesday afternoon. Smith pleaded guilty to the stalking charge. All other charges were dropped. He was put on probation for three years.

When Smith filed a motion in 2000 to have his weapon returned, the court agreed under this condition: "permitted to hunt and carry sporting weapons for purpose of hunting."

In a 2004 bankruptcy filing, Smith reported to the court that he owned one gun -- a .30-06 Ruger hunting rifle.

Smith's financial problems continued after his personal bankruptcy. In 2007, his mortgage company, Washington Mutual, filed foreclosure proceedings against him and his wife.

From his bankruptcy petition in 2004, it's also known that Smith is a contractor who owned Smith Construction.