A 27-year-old man was charged with murder on Monday in the fatal shooting of an Illinois pastor during Sunday service.

Terry J Sedlacek of Troy, Illinois, was charged with first-degree murder for allegedly shooting the Rev Fred Winters, the pastor of First Baptist Church of Maryville. The pastor was shot three times and later died of a single gunshot wound to the chest.

Prosecutors also charged Sedlacek with two counts of aggravated battery for alleged stabbings to church members Terry Bullard and Keith Melton, said Stephanee Smith of the Madison County state's attorney's office, according to The Associated Press.

The injuries of the two parishioners were not life-threatening, Illinois State Police said.

Sedlacek is being treated for self-inflicted knife wounds at a St Louis hospital and is in serious condition. A judge has ordered him held without bond, AP reported.

State police have still not offered a possible motive in the shooting.

The gunman, however, had written "death day" on Sunday in a planner that was found in his home.

Sedlacek reportedly suffered from mental illness caused by Lyme disease. His mother told the St Louis Post-Dispatch, which profiled his disease in August, that he began acting strangely in high school after he was bitten by an infected tick.

Police say the gunman walked down the aisle of the church, exchanged words with Winters and then started shooting until his gun jammed.

Melton, who was at the end of an aisle seat, told AP in a video interview that the gunman caught his attention as he walked down the aisle because things "seemed out of place".

Winters, who was preaching from the pulpit, paused his sermon and asked Sedlacek, "Good morning. What can I do for you?" recalled Melton.

Sedlacek then opened fire, first hitting Winters' Bible and then the preacher himself.

Bullard and Melton tackled the gunman to the ground as he pulled out a knife. All three were wounded in the scuffle.

Sedlacek had 10 rounds of ammunition in a handgun and was carrying two more 10-round magazines in his pocket, enough ammunition to kill 30 people, a prosecutor said on Monday, according to AP.

Despite the ordeal, Melton told AP he would pray for the gunman.

"Pastor Fred would not be honoured if we hated this man. God would not be honoured," he said. "We're going to pray for this man and pray for his salvation."

Many leaders in the Baptist community have responded to news of the shooting with grief and prayers.

Winters was former president of the Illinois Baptist State Association and an adjunct professor for Midwestern Baptist Theological Seminary.

Thom S Rainer, president and CEO of LifeWay Christian Resources, who taught Winters at The Southern Baptist Theological Seminary, remembered him as a "friend and co-labourer in ministry."

"My heart breaks for Fred's family, and I am already praying for them in this time of shock and grief. We also pray for First Baptist Church of Maryville. They have lost a great pastor and a dear friend," Rainer said in a statement.

SBTS president Albert Mohler wrote on his Twitter that he was praying for Winters' family. "God will vindicate," he said.

The shooting happened in the church sanctuary, a place associated with worship and love, not violence. Many pastors are now reevaluating their church security.

"Sadly, churches need protections against random acts of violence. Ours has none right now, but we probably need to have this conversation," the Rev Chuck Warnock of Chatham Baptist Church in Chatham, Virginia, wrote on his blog.

Winters' church will be holding visitation hours from 2 to 8pm Thursday. A funeral service will be held at the church on Friday at 10:30am. A graveside service to follow will only be open to Winters' family members.