The Algerian capital, Algiers, has had its biggest street demonstrations in over a decade in recent days as crowds protested against Abdelaziz Bouteflika seeking a fifth term as president after 20 years in power.

Students are expected to lead fresh demonstrations on Tuesday after several days of angry protests that began on Friday when tens of thousands of people took to the streets in towns and villages across the country, including the capital.

It is rare for protests to be tolerated by authorities, particularly in Algiers, where demonstrations have been banned since 2001.

On Sunday, hundreds of people demonstrated in Algiers as police sprayed teargas, brought in water cannon and rounded up protesters, an AFP journalist on the ground reported. State radio journalists complained of a blackout imposed on media coverage.

Bouteflika, 81, has been in office since 1999, but he is in ill-health and has been seen in public only a handful of times since suffering a stroke in 2013. A veteran of Algeria’s independence struggle against the colonial power France, he is the country’s longest-serving president. An announcement was made earlier this month by the ruling National Liberation Front party that he would attempt to run again in elections on 18 April.

After the first demonstrations on Friday, with large crowds in Algiers and several villages and towns, security forces arrested more than 40 people. Policed fired teargas to block a march on the presidential palace in Algiers, prompting demonstrators to respond by throwing stones, international news agencies reported.

Riot police confront protesters in the largest demonstrations in Algiers in a decade. Photograph: Mohamed Messara/EPA

State media have been silent on the protests and national radio journalists at the weekend complained they were being prevented from reporting on the opposition to Bouteflika.

In an unsigned letter to management, they attacked the “decision by the hierarchy to ignore” the rallies and deplored the skewing of coverage in favour of the president.

On Saturday, Meriem Abdou one editor at the national radio station said she had quit in protest over the restrictions being placed on journalists.

On Sunday, protesters took to the streets in response to a call by the opposition group Mouwatana. Some demonstrators chanted: “Algeria, free and democratic.”

The Mouwatana coordinator Soufiane Djilali told AFP that 15 members of the group had been detained along with “dozens” of other people. These figures could not be independently verified.

Several parties, trade unions and business organisations have already said they will back Bouteflika’s presidential bid. A weak and divided opposition faces difficulty in mounting an electoral challenge.

Supporters of Bouteflika have emphasised the risk of unrest. Algerians have bitter memories of a decade of civil war in the 1990s in which 200,000 people were killed. The war was triggered after the army cancelled an election that Islamists were poised to win in 1991.

Abdelaziz Bouteflika, 81, is in ill health and has rarely been seen in public since suffering a stroke in 2013. Photograph: Sidali Djarboub/AP

“Do you want Algeria to go back to years of tears and blood?” said the leader of the powerful UGTA trade union, Abdelmadjid Sidi Said, in televised comments.

Bouteflika has not directly addressed the protests. State media quoted a letter in his name read out at a government oil and gas industry event in the southern town of Adrar as saying: “Continuity is the best option for Algeria.”

Algeria, with its history of violent internal conflict, did not see the escalation of an Arabspring-inspired movement in 2011, despite uprisings in nearby Tunisia, Libya and Egypt.

Strikes and protests over social and economic grievances are frequent in Algeria but are generally localised and do not touch on national politics.

Algeria has a young population – 45% of its people are under 25. But more than a quarter of Algerians under 30 are unemployed, according to official figures, and many feel disconnected from a ruling elite made up of veteran fighters from Algeria’s 1954-62 war of independence with France.

• The first image of this article was changed on 28 February 2019 because an earlier picture was of crowds in Paris, not Algiers.