A Mexican rapper has confessed to disposing of the bodies of three missing film students by dissolving them in acid, state prosecutors say.

Christian Palma Gutiérrez, better known as QBA, said he had been paid 3,000 pesos ($160; £115) a week by the Jalisco New Generation drug cartel.

Investigators say he told them it had not been the first time he had disposed of bodies in this way.

The rapper will be charged with aggravated kidnapping.

QBA reportedly told investigators a friend had recruited him to work for the cartel three months before his arrest.

"He has participated in three other previous murders," chief investigator Lizette Torres told AFP news agency.

So far, QBA and one other suspect have been arrested in connection with the kidnapping and murder of the three film students.

Police are still searching for five other suspects.

Why were the students abducted?
The students were kidnapped on 19 March in the town of Tonalá, in western Jalisco state.

They were seized by a group of men disguised as police when their car broke down on a motorway.

The students have been named as Javier Salomón Aceves Gastélum, Jesús Daniel Díaz and Marco Ávalos, all in their 20s.

Investigators think the cartel mistook them for members of a rival gang.

Ms Torres said the three had been filming at a ranch which was being watched by cartel members who were waiting for a rival gang leader.

After they were seized, Javier Salomón Aceves Gastélum was questioned under torture by the cartel members. When he died of the blows inflicted on him, the cartel members decided to kill his two friends as well.

According to the investigators, QBA received a call that same evening telling him to dispose of their bodies.

Who is QBA?
Ms Torres said QBA's music videos and his YouTube channel, which has almost 125,000 subscribers, were being investigated by officials for further clues.

The videos are mainly shot in poor neighbourhoods of Guadalajara, the state capital of Jalisco, and feature youths brandishing guns and taking drugs.

One of them shows a bloodied man lying on the floor with his hands tied.

Mexico experienced its most violent year in 2017 with more than 25,000 murders, official figures suggest. It is the highest annual tally since modern records began.

Organised crime accounted for nearly three-quarters of those murders.