At least 21 people were killed after security forces engaged in a gun battle with suspected cartel members on Saturday, Nov. 30, in Villa Union, a town in Coahuila State near the U.S. border with Mexico, according to Fox News.

The shootout happened around noon. A group of heavily armed gunmen stormed the town of 3,000 residents in a convoy of trucks, they attacked local government offices and prompted state and federal forces to intervene.

Ten alleged members of the Cartel of the Northeast were killed in the response to an hourlong gun battle. Four police officers were killed in the initial confrontation and several municipal workers were missing, Coahuila State Gov. Miguel Angel Riquelme said.

Security forces killed seven additional members of the gang, bringing the death toll to at least 21, the state government said on Sunday.

The state had acted “decisively” to take back the town, Riquelme told reporters. The City Hall of Villa Union was riddled with bullet holes in the gun battle.

A damaged pickup marked with the initials C.D.N., that in Spanish stand for Cartel of the Northeast, is on the streets after a gun battle between Mexican security forces and suspected cartel gunmen, in Villa Union, Mexico, Saturday, Nov. 30, 2019. (Gerardo Sanchez/ AP Photo)

The governor also told reporters that police had identified 14 vehicles involved in the attack and seized more than a dozen guns. He said that security forces will remain in the town for several days to restore a sense of calm.

“These groups won’t be allowed to enter state territory,” the government of Coahuila said in a statement.

President Trump said in an interview aired on Tuesday that he planned to designate the cartels as terrorist organizations.

Mexican officials worried it could lead to unilateral U.S. intervention in its territory, according to The Federalist Paper. U.S. Attorney General William Barr will visit Mexico next week to discuss cooperation over security.

“I don’t think that Mexico needs intervention. I think Mexico needs collaboration and cooperation,” Riquelme said. “We’re convinced that the state has the power to overcome the criminals.”

The governor said the number of people missing was unspecified, including some who were at the mayor’s office, according to the paper.