Police and rescue crews are combing the area around a lake near Whistler after a personal item belonging to a missing 25-year-old was found near the lake.

Alison Leanne Raspa was last seen on Wednesday at 11:30 p.m. as she was leaving the Three Below Restaurant and Lounge in Whistler Village. The next day, police discovered her personal item near a lake located outside Creekside Village.

"We ask anyone who may have any information as to Alison's movements from the time she was last seen leaving the Three Below bar and the time her personal item was located at Alpha Lake Park… to call police immediately," Sgt. Annie Linteau said in a release.

An RCMP diver searched the frigid lake waters Sunday afternoon while members of Whistler Search and Rescue Society combed the shores looking for clues. Police also attempted a sonar search but said results were inconclusive because of obstruction from weeds in the lake.

Police asked for the public's assistance to locate the missing woman on Friday after pursuing "a number of investigative avenues." Linteau said police are "very concerned" for Raspa's safety.

Raspa's coworkers at the Westin in Whistler reported her missing when she didn't show up to work on Thursday.

One of her colleagues from the hotel, Raiko Kuidmaa, says everybody is worried about her.

"Nobody knows anything, which is really sad," he told CTV News. "Everybody's trying to help somehow."

He said he's hoping for the best—that she'll show up safe.

"Alison is a very, very nice girl," he said. "A little bit quiet or shy, but if you talk with her she's very open-minded."

According to posts by family and friends on Facebook, Raspa is originally from Australia but was living and working in Whistler.

The night Raspa went missing she was wearing a black jacket, a white and black striped shirt and black pants. She also had a blue backpack. She's described as white with long brown hair and blue eyes.

Anyone with information is asked to call Whistler RCMP at 604-932-3044.

With a report from CTV Vancouver's Scott Roberts