Demonstrators have taken to the streets in several Algerian towns to denounce President Abdelaziz Bouteflika's bid for a fifth term.

Security was tight Friday in the capital, Algiers, where hundreds of protesters headed to Martyrs Square in the city center.

The 81-year-old Bouteflika announced this month that he plans to seek a new term in April presidential elections despite serious questions over his fitness for office after a 2013 stroke left him largely infirm.

Other demonstrations have taken place in Oran, the country's second most important city, and in the northern towns of Akbou and Annaba.

Protesters are responding to anonymous calls on Algerian social media. Another demonstration is planned on Sunday in Algiers.