COLORADO SPRINGS, Colo. -- A gunman shot four staff members at a missionary training center near Denver early Sunday, killing two, after being told he couldn't spend the night. About 12 hours later and 65 miles away, a gunman fatally shot a parishioner at a megachurch and wounded four other people before a guard killed him, police said.

The police chief in Arvada, a suburb about 15 miles west of Denver where the mission workers were shot, said the shootings may be related to those at the Colorado Springs church but declined to elaborate. Arvada authorities said no one had been captured in the shootings there.

The gunman at the New Life Church in Colorado Springs was shot and killed by a church security guard after entering the church's main foyer with a high-powered rifle shortly before 1 p.m. and opening fire, Colorado Springs police chief Richard Myers said. Four others were wounded, Myers said.

Gunman killed

The church's 11 a.m. service had recently ended, and hundreds of people were milling about when the gunman opened fire. Nearby were parents picking up their children from the nursery.

Police arrived to find that the gunman had been killed by a member of the church's armed security staff, Myers said.

"There was a courageous staff member who probably saved many lives here today," Myers said.

Gov. Bill Ritter ordered state authorities to help investigate. The FBI and the federal Bureau of Alcohol, Tobacco, Firearms and Explosives were assisting, and officers combed the church campus looking for suspicious devices.

Three of the injured were taken to Penrose Community Hospital in Colorado Springs, said hospital spokeswoman Amy Sufak. One person was critical, she said. It wasn't known where the fourth injured person was being treated.

New Life was founded by the Rev. Ted Haggard, who was fired last year after a former male prostitute alleged he had a three-year cash-for-sex relationship with him. Haggard, then the president of the National Association of Evangelicals, admitted committing undisclosed "sexual immorality."

The New Life church is one of Colorado's largest with about 10,000 members. The mission training program in Arvada has a small office at the church's World Prayer Center on the New Life campus.

Security was higher

About 7,000 people were on the Colorado Springs campus at the time of the shooting, Boyd said. Security at the church had been beefed up after the early morning shootings in Arvada, he said.

That shooting happened about 12:30 a.m. at the Youth With a Mission center in Arvada, a Denver suburb, police spokeswoman Susan Medina said.

A man and a woman were killed and two men were wounded, Medina said. All four were staff members of the center, said Paul Filidis, a Colorado Springs-based spokesman with Youth With a Mission.

Arvada police chief Don Wick, asked whether he believed there was reason to think the shootings are related, responded, "Yes, there is reason to believe that."

Wick said the suspect spent several minutes speaking with people inside the dorm. Peter Warren, director of Youth With a Mission Denver, said the man asked whether he could spend the night. Several of them called on Tiffany Johnson, the center's director of hospitality.

"The director of hospitality was called. That's when he opened fire," Warren said.