Lawyers for jailed Tunisian opposition leader Rached Ghannouchi Thursday said his health was "critical" after reports the 85-year-old fainted and suffered severe exhaustion while barred from family visits.

Haifa Chebbi, the daughter of another jailed opposition leader, said she saw the former speaker of parliament lose consciousness due to the extreme heat in prison

The incident was witnessed by the daughter of Ahmed Nejib Chebbi, another prominent political prisoner.