Mar. 8: Mourners comfort each other in front of the First Baptist Church in Maryville, Illinois.
Pastor Fred Winters
March 8: Maryville First Baptist Church is seen in Maryville, Ill., after a man shot a pastor to death and injured others.
March 8: Onlookers watch as authorities investigate the scene at Maryville First Baptist Church.
An Illinois pastor was shot and killed, and two parishioners injured after an unknown gunman opened fire during Sunday services at the First Baptist Church in Maryville, Ill.
The gunman walked down the church aisle and briefly spoke to the pastor before shooting during the 8:15 a.m service. Rev. Fred Winters used the Bible he was reading from to shield himself from the first round of bullets being pumped at him, a parishioner told FOX News.
The gunman's .45 caliber semi-automatic pistol jammed after the fourth shot was fired. The suspect then started stabbing himself with a four-inch knife, Ralph Timmins of the Illinois State Police told the St. Louis Post-Dispatch.
Timmins said the gunman slashed two parishioners when they tried to subdue him.
The newspaper reported late Sunday a source close to the case confirmed the gunman as Terry Joe Sedlacek, 27, who developed mental illness after Lyme disease attacked his brain.
Rev. Winters was shot three times, and was pronounced dead at Anderson Hospital.
The gunman and one stabbing victim, 39-year-old Terry Bullard, underwent surgery at St. Louis University Hospital, spokeswoman Laura Keller said. Bullard was in serious condition, she said.
The other victim, Keith Melton, was treated and released from Gateway Regional Medical Center, spokeswoman Kate Allaria said. A man who answered the phone at a listing for Keith Melton in Troy identified himself as Melton's stepson and said Melton had been stabbed but was going to be fine.
Illinois State Police say they are 99 percent sure they have the identity of the suspect, but have not released his name pending possible charges. They have confirmed he is 27-years-old and from Troy, Ill.
The Rev. Mark Jones, another pastor at First Baptist, said he did not recognize the gunman, who Jones saw briefly before he pulled his weapon. Jones then went into an adjacent room and did not see the shooting, though he heard a sound like miniature fire crackers.
"We have no idea what this guy's motives were," Jones said outside the church. "We don't know if we'll ever know that."
Police said there were about 150 people in the church at the time of the shooting.
Linda Cunningham was sitting near the back of the church when the gunman walked up the aisle. She told the St. Louis Post-Dispatch she figured the man was confused about what time the service started because of daylight savings time.
Cunningham told the Post-Dispatch she, as well as others, didn't recognize the gunman.
Some parishioners believe the gunman used church bulletins to conceal his weapon.
"All you could see was confetti" Cunningham told the Post-Dispatch.
The church has an average attendance of more than 1,200 and was officially organized on March 4, 1945, according to their Web site.
The Associated Press contributed to this report.