BROWNSVILLE, Texas (Reuters) - U.S. authorities vowed on Tuesday to work with Mexico to hunt down the killers of a federal agent shot by suspected drug cartel hitmen in Mexico, as more than a thousand mourners gathered for his funeral in south Texas.
At least 1,200 people crammed into an events center in Brownsville to hear a Cathoic Mass for Immigration and Customs Enforcement agent Jaime Zapata, who was shot to death by unidentified gunmen on a highway in central Mexico a week ago in a bloody assault that also wounded a colleague.
Hitmen shot Zapata five times after forcing the agents' car off the road near San Luis Potosi. His colleague, Victor Avila Jr., survived and was flown back to the United States where he was treated for gun shot wounds to his leg.
"Together, the United States and Mexico will bring the long, hard arm of the law down on Jaime and Victor's shooters," ICE director John Morton told mourners packed into the events center for the agent's funeral.
"Together we will look after our people. Together we will continue to see that Jaime and Victor's work is done and that the rule of law triumphs over lawlessness and empty violence," he added.
U.S. law enforcement agencies are working with Mexican authorities to investigate the bloody assault, although officials have not confirmed if the agents were specifically targeted.
Federal, state and local police joined hundreds of mourners in the streets outside the events center, to accompany the funeral cortege taking Zapata's casket to a cemetery five miles away for burial.
A large video screen showed pictures of the life of the slain agent, a Brownsville native who loved to fish, travel to Mexico and barbecue with friends.
Zapata joined ICE in 2006. He worked with a human smuggling and trafficking unit in Laredo, Texas, before being sent to Mexico City to work on efforts to target drug traffickers whose violent turf wars have become a concern to both Washington and Mexico City.
More than 34,000 people have been killed in raging drug violence south of the border since late 2006, when President Felipe Calderon took office and ordered the army to smash the powerful cartels.
Zapata's murder was the most high profile attack on a U.S. federal agent in Mexico since the kidnap, torture and murder of Drug Enforcement Administration agent Enrique "Kiki" Camarena in 1985.
Officials said the two ICE agents were returning to Mexico City after meeting other U.S. personnel in San Luis Potosi, in central Mexico.
They were unarmed because U.S. law enforcement officers are not authorized to carry guns in Mexico.
U.S. Homeland Security Secretary Janet Napolitano and Attorney General Eric Holder also spoke at the funeral.
Writing by Tim Gaynor; editing by Robin Emmott and Greg McCune