Mr Karam, who was attorney general from 2012 to 2015 and led a widely-criticised 2015 investigation into the disappearances, has been charged with forced disappearance, torture and the obstruction of justice, the BBC reports.

A truth commission established by President Andrés Manuel López Obrador in 2018 — shortly after he came to power at the expense of Mr Karam’s rival party — last week identified the disappearances as “state crime” involving federal police and the Mexican army.

The 43 students, from Ayotzinapa Rural Teachers’ College, disappeared while travelling to Mexico City on hijacked buses to take part in an annual demonstration commemorating the 46th anniversary of the Tlatelolco massacre, in which Mr Karam’s Institutional Revolutionary Party (PRI) was also implicated.

In a statement, the PRI defended its former attorney general and accused the Mexican government of political persecution. The party tweeted: “Our absolute support with him. We will not remain silent before a government that uses the state apparatus against opponents.”