Video surveillance tapes from convenience stores where a missing University of Wisconsin-Green Bay student might have stopped are being reviewed for any clues to her disappearance, a police investigator said Tuesday.

Mahalia Xiong, 21, vanished early Friday after a night out with friends at a bowling alley and a sports bar, Lt. Todd LePine said.

Investigators have been probing Xiong's cell phone records, interviewing friends and family and retracing her steps, including using a helicopter to look for Xiong's car, LePine said.

Xiong, an officer with the UW-Green Bay Hmong Student Association, went with a group of friends to Ashwaubenon Bowling Alley about 10 p.m. Thursday, he said. The group left to go to the Time Out Sports Bar near Lambeau Field about 1 a.m. Friday and Xiong left her rented car, a white 1996 four-door Mercury Sable, at the bowling alley.

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The group returned to her car about 2 a.m. and Xiong was seen getting into the vehicle alone and driving off, LePine said.

She was apparently heading to her home on Green Bay's far east side, he said. Xiong had been drinking, he said.

"She was in good spirits," he said. "She seemed like a pretty good kid. She was well respected."

Xiong was driving the rental vehicle until her car was fixed at a shop in Sheboygan, LePine said.

Xiong had registered for classes as a senior this fall at UW-Green Bay, which has about 5,700 students, said Chris Sampson, a university spokesman.

Her parents live in Green Bay and she has an apartment in the city, Sampson said.

Xiong is described as 5-foot-tall, 105 pounds with a medium build. She has black hair and brown eyes and last was seen wearing a long-sleeved white shirt, blue jeans and black high-heeled shoes.

Her family is starting a reward fund for information about her whereabouts, LePine said.

Xiong is the second college coed in Wisconsin to disappear suddenly in recent weeks.

Last week, police discovered the body of Kelly Nolan, a 22-year-old University of Wisconsin-Whitewater student, in a rural area 10 miles south of Madison. She vanished early June 23 after a night out in downtown Madison.

Nolan had been living in a Madison apartment for the summer, and police have said they have no suspects in her death.

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