Mexican police have arrested a retired judge accused of tampering with evidence related to the disappearance of 43 Iguala more than a decade ago.

Lambertina Galeana Marín was president of the Guerrero State High Court when she disappeared in 2014.

The 79-year-old allegedly ordered CCTV footage to disappear, investigators say that was the key to the case.

She was arrested in the city of Chilpancingo three years after the warrant was issued.

The long-lost disappearance of 43 students - all attending the same teacher training academy in the town of Ayozinapa - has long been plaguing Mexico.

Despite several investigations over the past decade, what happened on the evening of September 26, 2014 is still unclear.

The remains of three students have been found, and the whereabouts of 40 students remain a mystery, although they are widely believed to have been killed.

The 2022 report of the Mexican government's mission to investigate the case found that it was a crime sponsored by state-sponsored by federal and state authorities.

According to the committee's report, local police worked with members of the criminal group to forcibly disappear the students.

The students went to Iguala to take the commander's bus and took them to the annual protests in Mexico City.

The Mexican government said police and a local criminal group called Guerreros Unidos (United Warriors) were warned of students' activities.

The report says Guerreros Unidos suspected that students on Iguala's bus had been infiltrated by members of a hostile criminal gang, Los Rojos.

It added that police officers and members of Guerreros Unidos subsequently installed several roadblocks in and around the city.

One of those roadblocks driven by local, state and federal police is on the street outside the House of Justice.

Two judicial employees told investigators that the palace's security cameras captured what happened to the barricade.

However, investigators said in 2015 that the video was never handed over to authorities, and that the footage was "lost" after officials tried to retrieve it about a year later.

Prosecutors have since claimed that Ms. Galeana ordered the video to be destroyed or deleted.

Ms. Gelina will face charges of forced disappearance, Mexico's security ministry said in an official statement.