The CBP did not provide many details about the incident, but law enforcement sources with knowledge of the matter told ABC News on Monday that they were looking into the possibility that it was an accident. Those sources did not speak about the cause of the injuries.

Texas Gov. Greg Abbott called it an “attack” and is offering a $20,000 reward for information leading to the arrest of a suspect in what his office described as a “murder.”

\"PHOTO:
John Moore/Getty Images
PHOTO: U.S. Border Patrol trainees take part in a weapons training class at the U.S. Border Patrol Academy on Aug. 3, 2017 in Artesia, New Mexico.
>

President Donald Trump tweeted his condolences on Sunday evening as he renewed his call to build a border wall.

“Border Patrol Officer killed at Southern Border, another badly hurt,” Trump tweeted. “We will seek out and bring to justice those responsible. We will, and must, build the Wall!”

The Border Patrol’s Special Operations Group and agents from CBP’s Air and Marine Operations are searching the area for potential suspects or witnesses, according to the CBP.

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