DENVER (AP) — In between his two deadly shooting sprees, church gunman Matthew Murray apparently posted furious threats on the Internet to kill Christians. But whether the warnings reached police before he struck again was unclear.

The warnings — and other anguished, despair-filled messages over the past few months — were posted by someone using the screen name ”nghtmrchld26.” The postings paint a picture of a home-schooled Colorado youth once affiliated with the Youth With a Mission program, as 24-year-old Murray had been.

”I’m coming for EVERYONE soon and I WILL be armed to the @%$ teeth and I WILL shoot to kill,” one threat posted Sunday by nghtmrchld26 said.

”God, I can’t wait till I can kill you people. Feel no remorse, no sense of shame, I don’t care if I live or die in the shoot-out. All I want to do is kill and injure as many of you … as I can especially Christians who are to blame for most of the problems in the world.”

At least one visitor to the site contacted the FBI promptly, before the second attack, the site’s administrator said. The FBI would not immediately confirm that Tuesday.

In all, nghtmrchld26 made at least 11 posts between the two shootings on a site run by the Association of Former Pentecostals, a nonprofit group that says it was created to help people who have left Pentecostal and charismatic churches.

”It’s time for me to head out and teach these (expletive) a lesson,” another message said. ”See you all on the other side, we’re leaving this nightmare behind to a better place.”

The last of the threatening messages was posted on the site at 9:55 a.m. or 10:55 a.m. — the time zone was not clear, said Joe Istre, the association’s site administrator and president.

Either way, that was several hours after Murray killed two people at Youth With a Mission, a training center for missionaries in the Denver suburb of Arvada, and at least two hours before he killed two more people at the New Life Church in Colorado Springs around 1 p.m.

An autopsy determined that Murray killed himself with a bullet to the head after he was brought down by gunfire from a volunteer security guard at the church, authorities said.

Denver FBI spokeswoman Rene Vonder Haar said the agency began an investigation immediately after receiving a phone call at 10:30 a.m. on Sunday. She refused to discuss the nature of the call but said the information was passed on to police in Arvada and Colorado Springs.

Colorado Springs police Sgt. Scott Schwall said police there did not learn the Murray family home’s address in Englewood until after the church shootings, and that a search did not begin until well after dark. The department did receive some information from the FBI well after the New Life shooting took place, he said, declining to say what the information was.

Arvada police spokeswoman Susan Medina confirmed that the FBI passed on information regarding the mission center shootings about 10:30 a.m. She would not discuss the information in detail but said ”we began work on that tip immediately.”

Medina said Arvada detectives did not go to Murray’s home and speak to his family until 3 p.m., well after the second attack. Medina said police cannot say with certainty who nghtmrchld26 is.

Murray was dismissed from Youth With a Mission in 2002 for what the training center has described only as health reasons. Youth With a Mission maintains an office at New Life Church’s World Prayer Center.

Murray’s parents donated $250 to the prayer center several years ago, New Life Senior Pastor Brady Boyd told The Associated Press. The church also discovered a visitors card indicating that Matthew Murray attended services several years ago, Boyd said.

But Boyd said no Murray family members were members of the church, and he downplayed the connections.

The gunman’s online rants make passing references both to New Life and founding pastor Ted Haggard, who was dismissed last year after a former male prostitute alleged a relationship with him.

The online threats appear to include whole passages lifted from a manifesto written by Eric Harris, one of the teens who carried out the 1999 massacre at Columbine High School — 13 miles (21 kilometers) from Murray’s hometown.

In the weeks before the shooting, nghtmrchld26 posted a number of messages about his own pain, despair and fury toward Christianity.

One post, called ”My YWAM Horror Story,” complained about being removed from the Arvada youth mission program.

”Why was I told that I couldn’t be a missionary because I wasn’t ‘social enough’? I was told that I was ‘an introvert,”’ nghtmrchld26 wrote. ”Everyone else got to go on their outreaches except for a few who lied about smoking (cigarettes). The authoritarianism and hypocrisy is outrageous.”

In an Oct. 6 post, nghtmrchld26 wrote about his anger at the church.

”We’ll make our own religion and be our own God’s instead listening to some abusive pedophile church like what I was raised in telling us who’s ‘saved’ and who’s not,” the person wrote.

”During this dark period I’ve realized this is not the way just to be a martyr. I can’t walk alone any longer and I’ll fight for the ones who can’t fight. If I lose at then least I tried. If I have to give my life you can have it.”