Both agents were transported to an area hospital for treatment, but CBP said Martinez later died of his injuries. Martinez's partner is in serious condition. "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", said a press release from the agency. According to social media posts, he is survived by his fiancee.
A reward is being offered for information that leads to an arrest in his death.
'We strongly believe rocks were what was used, ' NBPC Vice President Art Del Cueto told the station. The FBI has taken over the investigation.
Martinez's partner called for help.
Border Patrol agents opened the gate in the border wall at noon for an hour, allowing waiting family members from the U.S.to walk partly through and meet and embrace relatives in Mexico for a scant three minutes each before tearfully saying goodbye.
Trump says a second officer injured Sunday was "brutally beaten and badly, badly hurt" but "looks like he'll make it".
On Sunday, Trumped tweeted, "We will seek out and bring to justice those responsible".
Wisconsin rolls over MI 24-10 to remain unbeaten
Late in the third quarter, Wisconsin redshirt junior linebacker Andrew Van Ginkel smoked Peters into the ground on third down. The Wisconsin rushing offense is formidable, especially with freshman Jonathan Taylor , who is averaging 7 yards per carry.
Trump has been urging for the construction of the wall to stymie the flow of undocumented migrants into the United States since his presidential campaign. Ted Cruz (R-TX) released a statement calling it a "stark reminder of the ongoing threat that an unsecured border poses to the safety of our communities and those charged with defending them".
"We are grateful for the courage and sacrifice of our border agents who have dedicated their lives to keeping us safe", Cruz said.
Elected officials referred to it as an attack, with Gov. Greg Abbott tweeting that "resources must be increased to prevent these attacks in the future".
Texas is offering a $20,000 reward for information that leads to the arrest and conviction of the person or people who killed a US border agent and injured another.
Border patrol records show that the Big Bend region, where the apparent attack took place, only accounts for 1% of apprehended migrants.
It was the sixth time that the gate has opened since 2013, allowing people from the US and Mexico who can not legally cross the border to visit without fear of deportation.