Police were still trying to piece together a timeline in the arduous investigation of the Friday shootings that began in Frankstown Township and spanned five crime scenes within a 1.5-mile radius.
A woman decorating a church hall for a children's Christmas party was among those killed. Three state troopers were injured.
Authorities haven't released a motive for the shootings.
"It's going to take us some time to put this all together ... and know exactly what occurred," said Lt. Col. George Bivens, a deputy state police commissioner.
Police did not release the names of the victims or the shooter, though they did say the man lived in Blair County, where all the shootings occurred. Clergy planned a prayer vigil Saturday for the victims, which included the woman at the Juniata Valley Gospel Church.
The gunman and the victims weren't related, though the victims may have been, at least distantly, Blair County District Attorney Rich Consiglio said.
Troopers were responding to a 911 call of a shooting in the township at about 9 a.m. Friday when they heard calls reporting at least one other shooting elsewhere, state police said.
The three troopers, in patrol cars, were injured in a pursuit that began after the gunman, driving a pickup truck, fired at them, police said. One trooper injured a wrist and then was hit in the chest but was saved by body armor.
A second trooper was injured by glass fragments in his eye and bullet fragments that hit him in the forehead, Bivens said.
The gunman was killed during a final exchange of gunfire after ramming his truck head-on into another police cruiser, authorities said. It was after that crash that the trooper shot in the wrist also was hit in the chest.
The third trooper suffered minor injuries from the head-on crash, Bivens said. More than one weapon was seized from the truck, Bivens added, but he declined to offer more specifics.
"I think we have three very fortunate state police members tonight," Bivens said Friday. "We are very thankful for the fact that they survived this attack. Someone was watching over them."
Besides the woman, one man was shot at a home and the other man was shot at a crash site where the gunman had used his truck to strike another vehicle, Bivens said.
But relatives of the victims said they were told the woman at the church was the first person shot, the Pittsburgh Tribune-Review reported. The gunman then shot two men in the driveway of a home after a confrontation at a stop sign, one of the men's cousins, Marie Brenneman, told the newspaper.
"This person went to their driveway with a pistol, pointed at them and started shooting," Brenneman said.
She said both men were the shooter's neighbors in the tiny village of Geeseytown, about 70 miles west of Harrisburg, the state capital.
"They were uneasy around him," she said.
The woman at the church had cooked food the day before for the funeral of the church's longtime pastor, said the Rev. James McCaulley, his brother. The church still was reeling from the death of the Rev. David McCaulley when the woman returned to decorate its hall, and bullets ripped through a window, he said.
The gunman then entered and shot one of two women before he left, the Rev. James McCaulley said.
Police identified the five crime scenes as the church; a home and ground around the home; a crash site where another victim was killed; the point in the road where the gunman opened fire on the troopers; and where the final encounter occurred after the truck collided with the police cruiser.
Bivens said investigators don't know if the victims were picked at random.
McCaulley, who is the pastor of another church about 50 miles from the site of Friday's carnage, said his older brother began leading the Frankstown church in 1954.
"He preached his last sermon at the church in October before he fell ill," McCaulley said.
The church, which lists about 150 members in an online ad posted this month seeking an associate pastor, is close-knit, and the woman killed Friday was among its more active members, McCaulley said. She had made food for him to take home Thursday since his wife had died this year, he said.
"The only thing I can say good at this time is that (the gunman) didn't do this 24 hours earlier when there was a big crowd in the church hall," McCaulley said. "We're devastated."