A man stands on a hill above Columbine High, where a cross and makeshift memorial honor those killed in the massacre
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Listening After Littleton
CNN IN-DEPTH SPECIAL:
Are schools safe?

May 3, 1999
Web posted at: 3:39 a.m. EDT (0739 GMT)

LITTLETON, Colorado (CNN) -- Amid long days of grieving, alone and in groups, the students and teachers of Columbine High School return to classrooms on Monday, less than two weeks after a school massacre left 15 people dead.

Columbine's nearly 2,000 students will finish out the year on the campus of an old rival, Chatfield High, while investigators continue to examine Columbine, now a massive crime scene after the April 20 killings.

Chatfield students will attend class in the morning, and Columbine students, in the afternoon. The high schoolers, most of whose bookbags were left inside Columbine, three miles away, have been given new bags filled with donated supplies.

Columbine is not scheduled to reopen until fall.

Carrying four guns through the booby-trapped halls and rooms of Columbine, suspects Eric Harris, 18, and Dylan Klebold, 17, killed 12 students and one teacher in the massacre, before killing themselves.

Jefferson County District Attorney Dave Thomas has said there is no evidence that anyone other than Harris and Klebold was responsible for the killings. Police found more than 50 unexploded devices at the school, which had led authorities to focus on the possibility of a conspiracy.

Over the weekend, Thomas said he expects charges to be filed against a man who sold or otherwise provided the shooters with the TEC-DC9 semi-automatic handgun used in the attack.

The man is expected to surrender to authorities Tuesday. There is no indication he knew how the gun was going to be used, officials said.

"We have a statute that prohibits the sale or transfer of handguns to juveniles and that will be the nature of the charges," Thomas said.

As the investigation continues, authorities have not ruled out the possibility that others could be charged. Some 150 investigators are assigned to the case, authorities said.

Deputy Sheriff Troy Gardalen said Sunday that the parents of Klebold were "very cooperative" in an hour-and-forty-five-minute interview with investigators. Thomas and Susan Klebold met with authorities Friday to answer questions about their 17-year-old son.

The parents of the other gunman, 18-year-old Harris, have refused to talk with investigators unless they are granted immunity from criminal prosecution.

At a memorial service Sunday, Columbine principal Frank DeAngelis assured the 3,000 students, parents and teachers gathered at the scenic Red Rocks Ampitheater outside Denver that the school will move forward despite the tragedy.

"We survived. We will prevail. We have hope to carry on because we were Columbine, we still are Columbine, and we will be an even stronger Columbine from this day forward," DeAngelis said to applause.

"I will not allow this tragedy to erase 27 years of excellence that Columbine represents," he said.

The sun shone, and the mourning crowd was spared the rains that have deluged the area since shortly after the massacre.

Friends of the 12 slain students and Coach Dave Sanders told bittersweet memories of their friends. Two teachers unfurled a banner in honor of all Columbine students that read "You are our heroes."

"Dave Sanders lives in my heart and in my mind," said one mourner.

As he heads back to class, sophomore Matt Hill, 16, said he's not worried about safety.

"I don't believe it's going to happen again. I wasn't afraid when it was happening just because God was was here to take care of me."

"I want to go back for sure," said Tiffany Typher, an 18-year-old senior wearing a "CHS" ribbon in her hair. But, she said, "I don't want to go to Chatfield. I'd rather go back to Columbine, just to have closure."

The Associated Press contributed to this report.