Updated

Police are searching for a missing 19-year-old woman who was last seen by friends walking into a restroom at a Colorado nightclub.

Kenia Monge, of Aurora, Colo., disappeared early Saturday morning after a night of drinking with friends at The Lavish Bar in downtown Denver, authorities said.

Witnesses told police that Monge left her cell phone and purse on a table before walking away to use the club's restroom.

A spokesman for the Denver Police Department told FoxNews.com that the last possible sighting of Monge was at a gas station at approximately 3:00 a.m. Saturday.

Police spokesman Sunny Jackson said that a man, whom he did not identify, claims to have offered Monge a ride home. The man told police that when he stopped at a gas station to buy cigarettes, Monge walked away with a different man, Jackson said.

"Our biggest concern is locating her," he said, adding that police are actively questioning the man who claims to have driven her in his vehicle.

"We’re not sure what he is at this point," Jackson said when asked if the man was a suspect. "It's an open investigation."

The legal drinking age in Colorado is 21. Jackson said that police are also investigating the nightclub and looking into what kind of ID, if any, Monge was carrying when she visited the club with two friends.

The woman's stepfather, Tony Lee, said in an interview with Fox 31 that he believes Monge was drugged and taken against her will.

"She would not get into that vehicle in a million years in my opinion if she was in her right mind," Lee told the station. "There's never been any drug issues. There's never been any runaway issues, any mental health issues ...She's always been a good girl."

Monge, who moved to the U.S. from Honduras when she was 12, graduated from Cherry Creek High School last June. She is described as 4-foot-11, weighing 115 pounds. Police say she was last seen wearing a black skirt, black jacket and red high heels.

Anyone with information on Monge's whereabouts is being urged to call the Denver Police Department at 720-913-2000.