DENVER -- Lakewood police have issued an "attempt to locate" 16-year-old Amber Nicole Westbrook.

She was last seen last Tuesday morning, Sept. 25, at the Middle College of Denver, near 29th and Federal, where she took classes.

Lakewood police said Westbrook may be with 40-year-old Matthew "Matt" Preston Caulk.

Caulk has been convicted of sexual misconduct with a minor in Washington state. He is wanted by the U.S. Marshals Office for failure to register as a sex offender in Montana. He is also wanted for failure to register in Lakewood, Colo.

Caulk was last seen with another unknown person in a dark green Volkswagen Golf at 613 Urban Court in Lakewood last Wednesday.

He may also be driving a red 2000 Mercury Cougar with expired Nebraska license plates.

Westbrook is described as 5'7", 170 pounds with blond hair and blue eyes. She has pierced ears and no tattoos.

Lakewood police told 7NEWS they do "not have any evidence of criminal behavior" and are investigating this as a possible "runaway/missing person."

If you see Westbrook or Caulk, call the Lakewood Police Department at 303-987-7111.