MEXICO CITY - A U.S. Immigration and Customs Enforcement agent was killed and another wounded while driving through northern Mexico Tuesday, in a rare attack on American officials in this country which is fighting powerful drug cartels.
Homeland Security Secretary Janet Napolitano said one agent was critically wounded in the attack and died from his injuries. The second agent was shot in the arm and leg and remains in stable condition.
The department did not release their names.
"I'm deeply saddened by the news that earlier today, two U.S. Immigration and Customs Enforcement (ICE) special agents assigned to the ICE Attache office in Mexico City were shot in the line of duty while driving between Mexico City and Monterrey by unknown assailants," she said.
U.S. and Mexican officials said they were working closely together to investigate the shooting and find those responsible.
"Let me be clear: Any act of violence against our ICE personnel - or any DHS personnel - is an attack against all those who serve our nation and put their lives at risk for our safety," Napolitano said. "We remain committed in our broader support for Mexico's efforts to combat violence within its borders."
The two agents were driving in the northern state of San Luis Potosi when someone opened fire on them, according to reports.
San Luis Potosi police said gunmen attacked two people a blue Suburban on Highway 57 between Mexico City and Monterrey, near the town of Santa Maria del Rio, at about 2:30 p.m.
Police said one person was killed and another was flown to a Mexico City hospital, though they couldn't confirm the victims were the ICE agents.
Arturo Sarukhan, Mexican ambassador to the U.S., spoke with ICE chief John Morton to express Mexico's condolences, according to a spokesman.
"This is a difficult time for ICE and especially for the families and loved ones of our agents. Our hearts and prayers go out to them. This tragedy is a stark reminder of the risks confronted and the sacrifices made by our men and women every day," Morton said in a statement.
Though Mexico is seeing record rates of violence from warring drug cartels and a crackdown on organized crime, it is rare for U.S. officials to be attacked. The U.S. government, however, has become increasingly concerned about the safety of its employees in Mexico amid the escalating violence.
In March, a U.S. employee of a consulate, her husband and a Mexican tied to the American consulate were killed when drug gang members fired on their cars as they left a children's party in Ciudad Juarez, across the border from El Paso.
The U.S. State Department has taken several measures over the past year to protect consulate employees and their families. In July, it temporarily closed the consulate in Ciudad Juarez after receiving unspecified threats.
1 US agent slain, 2nd wounded in attack inside Mexico