Mourners in Brownsville, Texas are paying their respects to the U.S. Immigration and Customs Enforcement agent who was shot dead last week in Mexico.
The mourners attended a public viewing Monday ahead of a religious service later in the evening for Jaime Zapata. He was killed and another agent wounded while driving between Mexico City and the northern city of Monterrey.
Zapata's funeral takes place Tuesday.
Homeland Security Secretary Janet Napolitano and Attorney General Eric Holder are scheduled to deliver remarks at the service, along with ICE Director John Morton.
Napolitano and Holder have formed a joint task force to assist Mexico in investigating the shooting. The Department of Homeland Security has said the full resources of the U.S. government are at the disposal of its Mexican partners in the investigation.
Zapata and Special Agent Victor Avila, Jr. were shot when they stopped at what appeared to be a military checkpoint, possibly set up by drug traffickers. The Mexican military said it had no checkpoints in that area.
Attacks on U.S. law enforcement personnel in Mexico are rare, despite increasing U.S. contributions to Mexico's fight against drug trafficking. The last high-profile attack there was in 1985, when a Drug Enforcement Administration officer was captured, tortured and killed while on an assignment.
Mexican military forces have been engaged in a brutal struggle against violent drug cartels. At least 34,000 people have been killed in Mexico's drug war since President Felipe Calderon took office in late 2006 and began cracking down on the cartels.
Some information for this report was provided by AP.