A man charged with murder escaped from jail early Saturday by climbing through an air conditioner vent, authorities said.

The vent was less than a foot wide, and authorities said Darryl Layne Norris had been losing weight since arriving at the Waller County Jail in April.

“We just found out he’s been slimming down a lot recently,” Waller County Sheriff Randy Smith said.

The jail noticed the 6-foot, 160-pound man was missing after performing a routine head count.

Norris, 26, and another man are charged with murder in connection with an April 17 convenience store robbery. Smith did not know if Norris was armed but considered him dangerous.

“He could be anywhere right now,” Smith said. “We just don’t know.”

The Texas Rangers were assisting, Smith said. Hempstead is about 50 miles northwest of Houston.