Jaime Zapata's death: One year later, still many unanswered questions There was a Mass on Wednesday in Brownsville, Tex., to honor the memory of Jaime Zapata, the Immigration and Customs Enforcement special agent who was ambushed and killed by drug cartel gunmen on a dangerous stretch of highway in central Mexico one year ago. ICE Special Agent Jaime Zapata, in an undated photo. (AP) But the family of the slain agent says they haven't gotten answers about how and why their son died. He and his partner, Victor Avila, were forced to the side of the highway by gunmen of the Zeta cartel. The doors on their government-issued, armored Chevrolet Suburban unlocked when the vehicle was put in park, allowing the assailants to wrench the door open wide enough to shoot into the vehicle, hitting both agents. It was also learned that one of the weapons used in the killing came from a pawnshop in Texas. Senior federal officials attended the services Wednesday, including ICE Director John Morton. Speaking of Zapata, Morton said, "He was the type of person who wanted to contribute something significant to this world." Morton spent the day with the Zapata family, who have been growing frustrated in the search for answers from ICE about what exactly happened to their son - so frustrated that their attorney had to resort to filing Freedom of Information requests. Zapata's parents, Mary Zapata-Muñoz and Amador Zapata Jr. - told the Brownsville Herald that they fear a cover-up. How many times was he shot? Zapata's mother said to the Herald, showing how much is still unknown. My son did not go there to kill anybody. Zapata was on temporary assignment in Mexico. He died on his ninth day there. Who sent him and why did they send him? Who was the person in charge of that? Would that person have gone? Would anybody else have gone by themselves? I don't think so," said his mother. There was a hearing Wednesday on Obama's 2013 budget, but Republican lawmakers took the opportunity to grill Homeland Security Secretary Janet Napolitano about the attack, the Houston Chronicle reports. "I think it's appropriate to remember that event and remember them here today in this committee," said Rep. Michael McCaul (R-Tex.). Madam secretary, there's been some speculation that the weapons used to kill Agent Zapata may have been possibly linked to Fast and Furious. Do you have any information to indicate there is a connection there? Fast and Furious was a federal operation that allowed weapons from the United States to pass into the hands of suspected gun smugglers so the arms could be traced. Many of those firearms were later lost track of, and some have been linked to crimes. "I have no information to that effect, no," Napolitano responded to McCaul's question. I don't know one way or the other.