MEXICO CITY – At least four suspected gunmen and a soldier died in a shootout in Nuevo Laredo, a border city in the northeastern Mexican state of Tamaulipas, the Defense Secretariat said.

An army patrol was attacked Friday on a street in Nuevo Laredo, located across the Rio Grande from Laredo, Texas, the secretariat said.

Gunmen traveling in six vehicles opened fire on the soldiers, who returned fire.

Five soldiers wounded in the shootout were taken to a hospital in the border city, the secretariat said.

Soldiers seized five assault rifles, 50 ammunition clips, 525 rounds of ammunition and a vehicle.

The army is carrying out “Operation Northeast” in Tamaulipas, Nuevo Leon, Coahuila and San Luis Potosi states in an effort to weaken the drug cartels that operate in the region.

The Gulf drug cartel has been waging a war in northeastern Mexico against Los Zetas, a band of army special forces deserters turned hired guns and drug traffickers.

The government said earlier this month that 12,903 people were killed in drug-related violence between January and September 2011 in Mexico, an increase of 11 percent from the same period in the prior year.

Mexico’s drug war death toll stood at 47,515 from December 2006 to Sept. 30.

The murder total has grown every year of President Felipe Calderon’s military offensive against the well-funded, heavily armed drug cartels.

Unofficial tallies published in December by independent daily La Jornada put the death toll from Mexico’s drug war at more than 50,000.