The U.S. Marshals and the Federal Bureau of Investigation joined the manhunt for an escaped killer from the Valley.

Gonzalo Lopez, 46, has been missing since Thursday when he assaulted the officer on a transport bus in Leon County and then fled from the vehicle,

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The escape happened near the small town of Centerville, where residents are being asked to stay indoors and lock their doors and vehicles.

Lopez was convicted of a 2005 murder in Weslaco where he kidnapped a man and demanded a ransom from the victim’s family.

When the victim, Lupe Ramirez, couldn’t produce the $40,000 he owed to a Mexican drug cartel, Lopez murdered him with a pickaxe, court records show.

In 2006, Lopez was sentenced to life in prison, only to escape 16 years later.

A school district shut down in response to the escape. .

The Texas Department of Criminal Justice announced a $22,500 reward for information that could lead to the capture of Lopez. Those with information on Lopez’s whereabouts are urged to call 911 or TDCJ OIG Crime Stoppers at 1-800-832-8477 or 936-437-5171.