DEKALB, Ill. -- In DeKalb, Ill., mourners have been standing in the rain, staring at five white crosses on a small hill before placing flowers in the snow in front of each one.

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The visitors held markers for long minutes in front of 16-foot-long remembrance boards crammed with messages, adding their own words. And a few kneeled in front of crime scene tape strung outside a Northern Illinois University lecture hall where a young man gunned down five students before turning the gun on himself.

Churches Remember Slain Victims

The tragedy hung over church services throughout the region.

At First Baptist Church in DeKalb, members pinned on red ribbons for a morning service.

The Rev. Joe Sanders prayed for the NIU community and the victims' families and asked God to help the gunman's family cope with the attack and their own grief of losing a son.

At least two churches in DeKalb held special services on the first Sunday since the rampage. And congregations in the victims' hometowns were coming together for services ahead of funerals planned for later this week.

The gunman, 27-year-old Steven Kazmierczak, killed five people and wounded 16 others in a lecture hall at NIU before taking his own life.

Seven people remain hospitalized after the attack. Three are in serious condition, one of them upgraded from critical. The other four are in fair condition.

Officials at NIU said classes will resume on Feb. 25, though Cole Hall -- where the shootings happened -- will remained closed until the end of the semester.

University officials promised a strong police presence and ample counseling for students and instructors when students return.

"We need to take care of ourselves and each other, reaching out to those of us who are struggling," Northern Illinois University President John Peters said in a statement.

"An act of violence does not define us."

Police Search Hotel

After initially calling a bomb squad to a DeKalb hotel, police recovered a laptop and a bag of ammunition Saturday they believe belonged to Kazmierczak.

The manager of the Travelodge hotel near the university's campus told police a man checked in three days before Thursday's shooting, paying cash and signing his name only as "Steven."

The man was last seen on Tuesday, hotel manager Jay Patel said.

The Chicago Tribune reported that authorities found a duffel bag that Kazmierczak had left in the room, the zippers glued shut. A bomb squad was called, but investigators found ammunition inside the bag, the newspaper reported, citing law enforcement sources.

Kazmierczak also left behind a laptop computer, which was seized by investigators, Patel told The Associated Press on Saturday.

Mystery Surrounds Gunman

As police continued their investigation into the mass shooting, details of a troubled past few close to Kazmierczak seemed to know about started to emerge.

University President John Peters said Kazmierczak had a "very good academic record" and no record of trouble before his graduation last year.

Former professor Jim Thomas described him as "the most gentle, quiet guy in the world," with a "passion for helping people." Thomas said Kazmierczak did confide in him once about "a kind of incompatibility discharge" from the Army in 2002. Thomas said Kazmierczak told him it wasn't for any behavioral issue but he was concerned it could be a "stigma" on his record.

There's also word that he spent more than a year at a Chicago psychiatric treatment center after high school. A former staffer said his parents placed him there because he had become "unruly" at home.

She said Kazmierczak used to cut himself and had resisted taking his medications.

Police say Kazmierczak had become erratic in the past two weeks after he stopped taking his medication.

On Friday, investigators interviewed Kazmierczak's father, Robert Kazmierczak, in Lakeland, Fla., and his former girlfriend in Champaign, Ill., the Chicago Tribune reported.

Investigators provided no details about what they may have learned. According to a law enforcement official who spoke on condition of anonymity because the case is still under investigation, authorities were looking into whether Kazmierczak and the woman recently broke up.

Kazmierczak 'Outstanding Student'

Police have yet to uncover a motive. Kazmierczak was an NIU graduate student in sociology in the spring of 2007, but was not currently enrolled, according to a release on the school's Web site.

The Chicago Tribune reported that the school honored the gunman two years ago for his research on the U.S. prison system. The research included a study of self-inflicted wounds among prisoners.

"He was an outstanding student. An awarded student," NIU Police Chief Donald Grady said. "Those he had communication with felt he was a very good student and a fairly normal, unstressed person."

Grady said that Kazmierczak was a graduate student in social work at the University of Illinois at Urbana-Champaign. Kazmierczak was taking some kind of medication, Grady said, but declined to name the drug or provide other details.

"He had stopped taking medication and become somewhat erratic in the last couple of weeks," Grady said.

Chris Larrison, an assistant professor of social work, said Kazmierczak did data entry for Larrison's research grant on mental health clinics. Larrison was stunned by the shooting rampage, as was the gunman's faculty adviser, professor Jan Carter-Black.

"He was engaging, motivated, responsible. I saw nothing to suggest that there was anything troubling about his behavior," she said.

In Lakeland, Kazmierczak's father briefly came to the door of his home Friday and asked reporters to leave him alone. Saying "this is a very hard time," Robert Kazmierczak said he would make no statements, then broke down in tears.

Kazmierczak grew up in the Chicago suburb of Elk Grove Village. He was a B student at Elk Grove High School, where school district spokeswoman Venetia Miles said he was active in band and took Japanese before graduating in 1998. He was also in the chess club.

Nobody answered the door Saturday morning at the Urbana, Ill., home of Kazmierczak's sister, Susan. But sobs could be heard through the door of the home, where a statement was posted:

"Our heartfelt prayers and deepest sympathies are extended to the families, victims, and all other persons involved in the Northern Illinois University tragedy. We are both shocked and saddened. In addition to the loss of innocent lives, Steven was a member of our family. We are grieving his loss as well as the loss of life resulting in his actions."

Scene Of The Shooting

Kazmierczak opened fire around 3 p.m. in a geology class inside an auditorium in Cole Hall. Police said the shooter did not fire all the ammunition he possessed.

Kazmierczak shot himself on the stage after a rampage that lasted just a few minutes and sent terrified students screaming, crying and running for the doors.

Journalism major Desiree Smith was at the back of the hall when the gunman opened fire. She said she dropped to the floor and kept telling herself, "Oh God, he's going to shoot me. Oh God, I'm dead."

The students killed have been identified as: Daniel Parmenter, 20, of Westchester, Ill.; Catalina Garcia, 20, of Cicero, Ill.; Ryanne Mace, 19, of Carpentersville, Ill.; Gayle Dubowski, 20, of Carol Stream, Ill.; and Julianna Gehant, 32, of Meridan, Ill.

Authorities don't know if the gunman targeted specific people or just shot at random.

Police said when the shooting was reported, officers were at the scene in "less than two minutes."

Kazmierczak had four weapons with him when he entered the lecture hall, according to Kevin Cronin of the Bureau of Alcohol, Tobacco, Firearms & Explosives: a Remington 12-gauge shotgun, a Glock 9 mm pistol, Sig Sauer pistol and Hi-Point .380 pistol.

Cronin said that the shotgun and Glock were purchased legally at a gun shop in Champaign, Ill., on Feb. 9. He bought the two other handguns at the same shop -- the Hi-Point .380 on Dec. 30 and the Sig Sauer on Aug. 6.

All four guns were bought legally from a federally licensed firearms dealer, Cronin said. At least one criminal background check was performed.

Peters said officials believe the shooter had no criminal record and had not been in contact with police prior to the shooting.