
A war-like battle broke out between cops and suspected cartel gunmen, leaving 21 dead, including four officers, in a small Mexican town that was left riddled with bullet holes.

The shootout erupted around mid-day on Saturday in Villa Union, a town of about 3000 residents, near the US border, and just days after President Donald Trump raised bilateral tensions by saying he would designate the gangs as terrorists.

The government of the northern state of Coahuila said state police confronted a group of heavily armed gunmen riding in pickup trucks through the town which is less than 50 miles from the US border. San Antonio, Texas, to the northeast, is about 3 1/2 hours away.

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Villa Union City Hall is riddle with bullet holes after a gun battle between Mexican security forces and suspected cartel gunmen on Saturday

At least 21 people were killed, four of them police officers, after an armed group in a convoy of trucks stormed the town in Coahuila state, prompting security forces to intervene, state Gov. Miguel Riquelme Solis said

A suspected cartel vehicle is show on the streets of Villa Union after the hour-long shootout

No explanation has been offered for the violence.

Standing outside the Villa Union mayor's bullet-ridden offices, Coahuila Governor Miguel Angel Riquelme told reporters the state had acted 'decisively' to tackle the cartel henchmen, Reuters reports.

Seventeen of them died in the gunfire.

In addition to the four cops who were killed, six officers were also left injured, the governor said.

The fighting went on for more than an hour.

Bullets began spraying Villa Union when a convoy of vehicles showed up in town, as seen in video clips posted on social media of the battle. Plumes of smoke also could be seen rising above the town.

The hour-long shootout in Villa Union, which only has 3000 residents, happened in a community less than 50 miles from the US border. San Antonio is to the northeast about 3 1/2 hours away

Bullet holes were everywhere in Villa Union, where an untold number of people were missing after the hour-long violence

A damaged pick up truck marked with the initials C.D.N., that in Spanish stand for Cartel of the Northeast. The cartel is suspected to be behind the hour-long shootout

Spent bullet casings lay on the street after the gun battle between Mexican security forces and suspected cartel gunmen

Reuters could not confirm the authenticity of the images.

Meanwhile, an unspecified number of people were also missing, including some who were at the mayor's office, the governor said.

There were at least 14 vehicles involved in the attack, and more than a dozen guns were seized.

A damaged vehicle is parked outside Villa Union City Hall. Among the missing were people who were believed to have been in the mayor's office when the town was sprayed with bullets

The governor said he believed the gunmen were members of the Cartel of the Northeast, which is from Tamaulipas state to the east.

The violence broke out after Mexico's President Andres Manuel Lopez Obrador on Friday said he would not accept any foreign intervention in Mexico to deal with violent criminal gangs after Trump's comments.

Lopez Obrador said Mexico would handle the problem, a view echoed by Riquelme as he spoke to reporters, Reuters reports.

Coahuila Governor Miguel Riquelme Solis, right, talks to a woman who said her son was missing after the gun battle

'I don't think that Mexico needs intervention. I think Mexico needs collaboration and cooperation', said Riquelme, whose party is in opposition to Lopez Obrador. 'We're convinced that the state has the power to overcome the criminals'.

Trump on Tuesday said he planned to designate the cartels as terrorist organizations, sparking concerns the move could serve as a prelude to the US trying to intervene unilaterally in Mexico.

US Attorney General William Barr is due to visit Mexico in the coming days to discuss cooperation over security.

Lopez Obrador took office a year ago pledging to pacify the country after more than a decade of gang-fueled violence.

A series of recent security lapses has raised questions about the left-leaning administration's strategy.

Criticism has focused on the November 4 massacre of nine women and children of US-Mexican origin from Mormon communities in northern Mexico, and the armed forces' release of a captured son of drug lord Joaquin 'El Chapo' Guzman under pressure from cartel gunmen in the city of Culiacan.

Coahuila has a history of gang violence, although the homicide total in the state that borders Texas is well below where it was seven years ago. National homicide figures are pushing record levels.