LITTLETON — Detectives investigating last week's massacre at Columbine High School questioned the 18-year-old girlfriend of one of the two gunmen on Monday, a woman police say may have purchased two of the weapons used in the killing spree.

Yet after a week of investigation, Jefferson County sheriff's officials insist they are not on the verge of arresting any possible accomplices of Eric Harris and Dylan Klebold, who took their own lives after killing 12 students and a teacher.

"We do not have any suspects, and you have to have a suspect to make an arrest," Sgt. Jim Parr told reporters Monday afternoon.

Investigators, though, have revealed more details from the diary of 18-year-old Harris, which lays out plans he and Klebold, 17, formed a year before the April 20 assault on Columbine.

Not only did the teens hope to destroy the high school, sheriff's spokesman Steve Davis said, but the duo also plotted to attack neighbors and crash a commandeered airplane into a city.

"They wanted to kill 500 people, hijack a plane and take it to New York City," Davis said.

Jefferson County's lead prosecutor said the plot to attack New York sounds like "some horrible fantasy."

"But we now know that at least the first portion of those planned activities were, in fact, carried out," District Attorney Dave Thomas told NBC's "Today" show.

Sheriff's officials say Harris and Klebold — armed with four guns and about 15 homemade bombs — walked into Columbine at 11:19 a.m. April 20, killing 13 people and injuring more than two dozen. Another 15 explosive devices were discovered in the suspects' cars.

Jefferson County Coroner Nancy Bodelson has ruled Harris and Klebold died of gunshots "consistent with self-infliction." Those who didn't survive the attack all died of gunshots, and not from bomb-related injuries.

On Monday, Bodelson announced neither Harris nor Klebold had drugs or alcohol in their system.

Because of the number of guns and explosives used in the attack, officials have speculated other suspects either knew of the teens' plans or were even involved in the preparation and staging of the assault.

Sheriff's investigators, who continue to comb the high school for bombs and evidence, have recovered four weapons — two 12-gauge sawed-off shotguns, a 9mm TEC-DC9 semiautomatic pistol and a Hi Point 9mm semiautomatic rifle.

An agent from the Bureau of Alcohol, Tobacco and Firearms last week said the two semiautomatic weapons were purchased separately at Denver-area gun stores within the last 18 months. The shotguns, which date to the 1960s, may never be traced.

Davis said the 18-year-old woman, reportedly Klebold's girlfriend, "was questioned about the handgun and the rifle." He wouldn't divulge whether the unidentified woman admitted to purchasing the weapons at a gun show, or whether she knew of Harris's and Klebold's plans.

"She was not held in custody," Parr said. "She was released. She is not considered a suspect."

School and law enforcement officials were on heightened alert Monday, in response to an e-mail missive purportedly authored by Harris that promised more violence on that date. Investigators said they don't believe the note, published Saturday in the Denver Rocky Mountain News, is authentic.

"We have not received any credible threats," Parr said Monday afternoon, acknowledging schools in the metro-area, including Boulder, and around the nation have been receiving a steady stream of prank bomb threats.

At 10 a.m. Monday, officials did evacuate Normandy Elementary School in Littleton after "someone found a backpack they couldn't account for," Parr said. Some of the explosives at Columbine were discovered in discarded backpacks.

A bomb squad found no explosives, and students returned to their classes.

Columbine students return to classes Thursday at Chatfield High School. Teachers return today to begin preparations.

Less than a half-mile from Columbine, 2,700 mourners at the Trinity Christian Center gathered Monday to remember business teacher William "Dave" Sanders, 47, who was shot twice in the chest as he shepherded students down a hallway to safety.

Funerals also were held Monday for students Lauren Townsend, 18, the captain of the girls' varsity volleyball team and a candidate for valedictorian; Daniel Rohrbough, 15, who was shot while holding an exit door open for fleeing students; and Cassie Bernall, 17, who became a born-again Christian two years ago.

A week after the Columbine students' rampage, mourners continued to pour into Clement Park, which abuts the high school, to pay tribute to people they never knew. An impromptu memorial that started last Wednesday as a few flowers around a tree has grown into massive — and still growing — spectacle.

"I think it's beautiful," said Highlands Ranch resident John Boyd. "To be here really hits you."

Two of the victims' cars remain at Clement Park, nearly every inch covered with signs and flowers. A lone red carnation peers out of the tailpipe of John Tomlin's pickup truck.

Dina Page, a 1987 Columbine graduate, left her black commencement robe to honor the dead.

Some left more simple messages, like the crudely cut construction-paper heart almost lost amid a floral sea. In the middle of the golden heart, the anonymous mourner wrote "Sorry."

The Associated Press contributed to this report.

April 27, 1999

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