Skeletal remains discovered in Mexican border state of Chihuhua taken to lab for possible identification, officials say.

Authorities in Mexico have uncovered 12 bodies in clandestine graves in the northern border state of Chihuahua.

Authorities discovered the skeletal remains in 11 graves in Ascension, about 180km (110 miles) west of Ciudad Juarez, near the border with the United States, the state prosecutor’s office said in a statement on Thursday.

The investigators started exploring the desolate site on December 18, and in subsequent days, they expanded the search area.

They eventually found 11 separate shallow pits into which a dozen bodies had been dumped.

The remains were taken to state forensic laboratories for possible identification and to determine, if possible, the causes of death.

Chihuahua has been hit for years by violence linked to organised crime as a route for drug trafficking and the smuggling of migrants to the US.

The state has recorded 3,927 missing persons since 1952, according to official figures.

Across Mexico, about 120,000 people are considered missing amid years of violence and instability.

The relatives of most of those missing people are largely left to look for their loved ones by themselves, and they frequently form volunteer search groups that go out into the desert looking for clandestine graves.

It was not known if any of those volunteer groups had helped authorities in locating the graves in Ascencion.