The Department of Homeland Security and the Department of Justice are forming a joint task force to find the assailants who killed a U.S. immigration agent and injured another while the two officials were driving in Mexico earlier this week.

Homeland Security Secretary Janet Napolitano announced the task force in a statement released after her meeting with U.S. Attorney General Eric Holder to discuss the incident. "This joint task force reflects our commitment to bring the investigatory and prosecutorial power of the U.S. Government to bear as we work with the Mexican Government to bring these criminals to justice," said Napolitano in the statement.

Officials say U.S. special agent Jaime Zapata died Tuesday after assailants opened fire on an SUV carrying the agents from Monterrey to Mexico City. Zapata was on assignment from his post in Laredo, Texas.

U.S. and Mexican officials said they were working together on the investigation.

The FBI will be heading the joint task force, said the statement from Homeland Security, “and will leverage the investigative capabilities of both agencies to work with Mexico in tracking down the perpetrators and swiftly bring them to justice.”