McALLEN, Texas (AP) - A father and son have been charged in the shooting of a U.S. Immigration and Customs Enforcement special agent in South Texas.

Pedro Alvarado and his 18-year-old son Arnoldo Alvarado are expected to appear before a federal judge Thursday morning. Prosecutors say they are charged with assault of a federal officer and knowingly using and carrying a firearm during a violent crime.

The agent was shot Tuesday morning while conducting surveillance in Hidalgo County, on the U.S.-Mexico border. The agent was taken to a hospital and required surgery for a gunshot wound.

Prosecutors in a statement say authorities detained three people after searching a home in Hargill. The third person, a minor, was turned over to state authorities.

Attorneys were not listed in online records for the two men.

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