Updated: 10/24/10 8:25 p.m.

Related: NIU Campus Awaits News On Missing Freshman

DEKALB, Ill. (CBS) – The unidentified human remains that were found in a wooded area of Prairie Park in DeKalb were discovered “early in the investigation” of a search for a missing Northern Illinois University student, local police said Sunday.

The Daily Chronicle reported DeKalb Police Chief Bill Feithen declined to elaborate as to how soon the remains were found but said, “I expect something more to come out in the next few days on that.” Feithen confirmed the information to CBS 2.

Late Saturday night, police said the mid-October disappearance of 18-year-old Antinette Keller of Plainfield had been reclassified as a death investigation.

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DeKalb police said human remains were found in Prairie Park, where Keller was headed. The Keller family had been notified of the discovery, Feithen said.

“We felt strongly enough about the developments and as well as the items that were located through the course of this investigation to bring us to this point,” Feithen said.

According to Feithen, investigators from the DeKalb County Major Case Squad recovered human remains and items consistent with property belonging to Keller in Prairie Park, south of Route 38 in DeKalb. Police are not releasing any details on the items recovered.

The remains have not been identified, and police are not confirming the condition of the remains. They have apparently been in the park for some time, perhaps since shortly after Keller’s disappearance, police said. The cause of death remains under investigation, Feithen said.

“We’re not prepared to give an estimate of right now of when we feel the remains can be identified,” Feithen said.

The remains were found in a densely wooded area, not a grassy area. A portion of Prairie Park remains cordoned off as officers continue the investigation, police said. Feithen said the area will likely be sealed off for the next day or two.

“It really depends on the evidence technicians,” he said. “It could be sooner.”

Investigators are actively pursuing leads in the case and are seeking information about any suspicious activity or persons in Prairie Park on or about the time of Keller’s disappearance.

Ben Yamamoto, a friend of Keller’s, says he went searching for her shortly after she disappeared — until police stopped him.

“They said it was too dangerous,”  he says.

The news of the Keller investigation sent shock waves through the NIU community. Students were walking in pairs or groups Sunday.  Other NIU students were hanging safety signs on dorms.

“I’m just really scared to be here right now,”  sophomore Aleesia Washington told CBS 2’s Dana Kozlov.

Anyone with information is asked to call police at 815-748-8407 or 815-753-8477 or Crime Stoppers at 815-895-3272.

More than a week has passed since Keller, a freshman on NIU’s DeKalb campus, last was seen. Keller, 18, left her dormitory at about 11:30 a.m. Oct. 14, when she reportedly told friends she was walking to Prairie Park.

An art portfolio she was initially thought to be carrying was found in her dorm room. Her family believes she left once with it, then returned it to her room before leaving for her walk.

The 2010 graduate of Neuqua Valley High School in Naperville is an art major at NIU.

Keller has been thoroughly enjoying her first semester of college life, said Mary Tarling, of Naperville, Antinette’s cousin, who is serving as a family spokeswoman.

“Every expression she’s given in the past six or seven weeks she’s been there was that she absolutely loved it,” Tarling said last week. “It fit her very well. She had just settled in and adored what she was doing.”

After DeKalb Police’s press conference Saturday, NIU President John Peters issued a statement, expressing deep concern and sadness.

“I know that all of the NIU community is distressed from this news. The outpouring of support in the search for Toni has been inspirational. Our community rallied together at the first indication she was missing, and I want to thank our students and the countless community volunteers who have been working tirelessly over the last week to get the word out about Toni’s disappearance,” Peters said in a statement. “Please keep the Keller family in your prayers during this very difficult time.”

The university has established an information hotline at 815-753-4NIU (4648). Calls will be answered from 9 a.m. to 6 p.m. Sunday. Parents and students who have questions are encouraged to contact the university’s information hotline. Students will also have access to counselors on campus until midnight Saturday and from 9 a.m. to 6 p.m. Sunday.

“The university is united behind meeting the needs of each and every one of our students as they cope with this news,” Peters said.

NIU officials and the NIU Police Department have implemented heightened campus safety and security measures. Late Saturday the university issued an advisory cautioning students to be extra careful as they move about the campus and the DeKalb community. Students were told to move about the community in groups of three or more.

NIU Police have increased their presence around the campus, and police are extending the normal “late night ride service” to a 4 p.m. to 8 a.m. schedule beginning Saturday. Students are being urged to use this service, especially if they are unable to find a group to travel with in and around campus.

Campus police are also making available security escorts for any NIU student, faculty or staff member in and around the campus on a 24-hour basis. Access to residence halls on campus will be restricted to hall residents only, with students needing their official NIU identification to gain access.

The Sun-Times Media Wire contributed to this report.

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