Was a Border Patrol agent beaten to death by immigrants in Texas? Or did he fall? The FBI is not sure

A mysterious incident last weekend that left one Border Patrol agent dead in west Texas and another critically injured is being investigated as a possible attack, officials said.

“There are a number of possible scenarios, but right now we are going to pursue it as an assault on a federal agent,” FBI Special Agent in Charge Emmerson Buie Jr. said during a Tuesday briefing in El Paso. "This is the most important investigation in the El Paso division of the FBI. We will be aggressively investigating all leads."

Agent Rogelio “Roger” Martinez, 36, a four-year veteran, was found with “traumatic head injuries” and broken bones at 11:20 p.m. Saturday near Interstate 10 about 12 miles east of Van Horn after responding to a triggered sensor, Buie said.

Martinez was sent to a hospital in El Paso and died from head injuries early Sunday. Autopsy results are pending.

The union representing Border Patrol officers said the two agents were attacked by migrants wielding rocks. Chris Cabrera, a union spokesman and veteran agent based in McAllen, Texas, said that calling the incident an assault was “insulting,” and he faulted federal officials for “downplaying” the incident instead of investigating it as a potential homicide.

“He didn't get punched in the neck. He's dead,” Cabrera said.

Martinez's partner, whose name has not been released, also suffered head injuries and remained hospitalized Tuesday in critical but stable condition, according to Victor Velazquez, acting chief of the Border Patrol's Big Bend sector, who called the agent “young and dedicated.”

“Our men and women deal with the constant presence of the unknown, ranging from those seeking illegal entry into the U.S., [to] smugglers of human cargo and/or drugs, transnational crime organizations and dangerous terrain,” Velazquez said.

The agents were found at the bottom of a 9-foot-deep culvert in an area known for drug activity, FBI and union officials said, leading to speculation that they might have fallen. The remote Big Bend sector, which includes almost a quarter of the southern border, is far from a migrant hot spot - mountains and a 510-mile stretch of the Rio Grande provide a natural barrier - but the Border Patrol reported an uptick last spring in drug smuggling all along the Texas border, with seizures of cocaine and heroin more than doubling.

Brandon Judd, president of the San Diego-based National Border Patrol Council union that represents agents, insisted the pair were attacked with rocks by a group of illegal border-crossers they were pursuing. Martinez's partner called for backup when he found him, but by the time backup arrived, the partner was also injured, Cabrera said.

By Tuesday, officials had canvassed the area where the incident occurred, about 110 miles east of El Paso, and were investigating the death as an assault, Buie said. He announced a $25,000 FBI reward for information leading to the arrest and conviction of those involved. That's in addition to a $20,000 reward announced by Texas Gov. Greg Abbott on Monday.

“There's no way he fell,” Cabrera said of the agent who died. “Border Patrol agents are like mountain goats. They don't fall. Especially two at the same spot.”

In the area where the agents were found, ditches run beside the roads, he said. “Even in the dark, they know it's there. These guys are familiar with that area. They work that area day in and day out.”

Martinez, an El Paso native, is survived by fiancee Angie Ochoa and his 11-year-old son, Sergio, officials said. He was the 125th Border Patrol agent to die in the line of duty, according to Velazquez, but the list includes natural and accidental deaths. Fatal attacks on agents are rare. Only a handful have occurred in the last decade, including shootings and an assault with a vehicle by a fleeing suspect.

After Martinez's death was announced, President Trump tweeted: “Border Patrol Officer killed at Southern Border, another badly hurt. We will seek out and bring to justice those responsible. We will, and must, build the Wall!”

On Monday, speaking at he White House, Trump again mentioned the incident, noting, “We lost a Border Patrol officer just yesterday, and another one was brutally beaten and badly, badly hurt. Looks like he'll make it, but very, very badly hurt.”

“We're going to have the wall,” Trump continued. “It's a part of what we're doing. We need it. It's rough territory. That's where the drugs are coming in. A lot of things are happening along the border - the southern border - and we're going to straighten it out.”

Asked about the president's comments, Buie said he had yet to brief Trump about the investigation.

Special correspondent Sierra reported from El Paso and Times staff writer Hennessy-Fiske from Houston.