The United States will close its consulate for one week to assess the security of its employees and consulate visitors in this Mexican border town after a shootout between drug gangs using machine guns, grenades and a rocket launcher.

In a statement from Mexico City late Friday, U.S. Ambassador Tony Garza (search) said "in light of this alarming incident and continued violence along the border, I have decided to suspend all operations except for emergency services for American citizens," for one week, beginning Aug. 1.

While the consulate is closed, "we will be gauging what should be a swift and certain response from the government of Mexico, to bring this situation under control," Garza said.

Garza's announcement came three days after the ambassador requested the renewal of a State Department travel advisory warning Americans about violence in Mexico, especially along the border.

Late Thursday, a group of armed men arriving in several vehicles fired machine guns at a home on Mexicali street in southern Nuevo Laredo (search). People inside the house are believed to have returned fire with powerful weapons of their own, and a massive shootout ensued.

No one was injured and no arrests were made. It was unclear why the home was targeted, though witnesses said it was a safe house used by drug smugglers.

Fire from what witnesses said was a rocket launcher caused part of the house to collapse and the walls left standing were marked with hundreds of bullet holes. A vehicle had been driven into the door of the adjacent garage.

A state policeman who asked not to be identified for fear of reprisals said investigators found the photographs of 14 city police officers and a list of officials "sentenced to death" in the house. The officer didn't reveal the names of the officers but said each photo had their names and nicknames, what post they have at the police department and maps with their home addresses.

Authorities also recovered threeAK-47 (search) rifles, two handguns, a grenade, ski masks, and hundreds of rounds of ammunition.

Several hours after that shootout, assailants sprayed another house, this one in the Madero neighborhood, one of the richest areas in Nuevo Laredo, with more than 100 bullets from automatic weapons. No injuries were reported, nor arrests made.

More than 100 people have been killed in this city across from Laredo, Texas (search), since January, including 15 police officers. Authorities have blamed the violence on a fight between Mexico's two most powerful drug gangs to control smuggling routes across the U.S. border.

Last month, Nuevo Laredo's police chief was gunned down hours after taking office, and police opened fire on a group of federal agents sent in to restore order, forcing President Vicente Fox's government to launch a purge of local officers.