TRACY, Calif. -- A Tracy couple have been taken into police custody after an emaciated 17-year-old boy ran into a fitness center Monday afternoon with a chain wrapped around his ankle with a padlock on it, a Tracy police spokesman said.

Kelly Layne Lau, 30, and her husband, Michael Luther Schumacher, 34, face one charge each of torture, kidnapping, false imprisonment, child endangerment, and corporal injury to a child, said police spokesman Matt Robinson.

A third adult suspect is also being sought in the case, Robinson said.

The police investigation began after the boy escaped from a home, Robinson said.

Wearing just boxer briefs, the 17-year-old burst into an In-Shape City at about 4 p.m. Monday, said Chuck Ellis, who works at the gym.

Ellis said the boy looked emaciated, bruised, scared and said, "Hide me. Please hide me."

Employees from the business alerted police, who arrived to question the boy, who did not know where he was at first, Robinson said

He eventually pinpointed a home and provided enough information for police to take the couple into custody, Robinson said.

The boy was taken to a local hospital, where he is in serious but stable condition and being treated for superficial wounds, officials said.

Two young children believed to be the couple's children were taken into the custody of child protective services, Robinson said.

A search warrant was served at the couple's house overnight, and evidence was pulled out this morning that will be compiled for the San Joaquin County District Attorney's Office, Robinson said.

The charges are related to the 17-year-old's case only, according to police.

The teen told gym employees that he was taken from a group home about a year ago, Ellis said. That group home is about 70 miles north of Tracy, in Sacramento.