A group of Islamists jailed in Mauritania for terrorist activity linked to Al-Qaeda announced a hunger strike on Sunday, demanding an end to "arbitrary measures" including being denied parole and having to pay to be released.

The inmates said in a statement to the media they were subject to increasingly punitive action, including having to stump up "excessive fines" on completing their sentences before being freed.

The statement cited the case of a Senegalese Islamist who was stuck in jail despite having served a three-year term because he could not afford a fine of five million Ouguiyas (12,000 euros, $20,000).

The Senegalese national, Bechir Sidibe, has been on hunger strike for several days and his health was rapidly deteriorating, the statement said.

Nouakchott's central prison houses 29 inmates serving up to 10 years each for various activities linking them to Al-Qaeda in the Islamic Maghreb (AQIM).

In their statement the group demanded the right to be considered for parole, "like every other normal prisoner", and for long-awaited judgements on their appeal applications to be announced more quickly.