Police in Mauritania said on Sunday they had arrested a man believed to be the organiser of the escape of four jihadist detainees from the central prison in the capital, Nouakchott, three weeks earlier.
In a statement posted on Facebook, they said a team from the General Directorate of National Security had arrested Mohamed T, known as Abou Ossama, in the city.
They said he had "orchestrated the escape of four prisoners convicted of terrorist crimes” and that he would be brought to justice after an investigation, but gave no further information about the man.
Five days after the four men broke out of prison on 5 March, one of them was detained alive while the other three were killed during attempts to recapture them.
This included Saleck Ould Cheikh Mohamedou, who was considered particularly dangerous. He was sentenced to death in 2011 for attempted car bombings against President Mohamed Ould Abdel Aziz and the French embassy.
American authorities, engaged in the anti-jihadist fight in the Sahel, believed him to be one of the organisers of the 2007 assassination of four French tourists in south-east Mauritania.
The escape of the four men had been a blow to Mauritania’s fight against Islamist radicals, particularly as Mohamedou had previously escaped from prison in 2015 before being recaptured.
The country has not seen an attack on its soil since 2011, when jihadism was spreading across the region.