A British national was arrested on Wednesday by the Mauritanian security forces when he tried to join the armed Islamist groups in northern Mali, through Mauritania's extreme eastern region of Mbiket Lahwach, a security source told Xinhua on Thursday.

Ahmed Chahine, 30, was first spotted in the historic town of Oualata (over 1,000 km east of Nouakchott) where he had presented himself as a researcher, before disappearing within 72 hours.

He was arrested by travellers who informed the security officers at Nema, in the east of the country, and they later proceeded to detain him. the source said.

When he was questioned by the Mauritanian security forces, he confessed that he was attempting to go to Timbuktu in northern Mali, to join the Islamic fighters allied to the al Qaida in the Islamic Maghreb (AQMI).