Police dispersed a small protest in central Algiers on Friday and stopped other small groups of demonstrators from reaching the city centre after weekly rallies since February that usually draw thousands.
It was unclear whether the small number of protesters who came out on Friday was due to Islam's Eid al-Fitr holiday or tougher government rules announced on Sunday.
Dozens of police rushed at the 100 people who tried to protest in central Algiers, forcing them to flee, a witness said.
In Bab al-Oued district, about 200 protesters marched but were unable to move past a police cordon to join groups elsewhere in the city, witnesses said.
Eid al-Fitr, when people traditionally gather with family or friends at the end of the Muslim fasting month of Ramadan, began on Thursday and continued on Friday.
On Sunday the Interior Ministry warned that it would no longer tolerate protests held without a permit that named the organisers and included starting and finishing times.
It laid down a challenge to the leaderless protest movement that erupted in 2019 when hundreds of thousands of people flooded the streets to protest then Abdelaziz Bouteflika's candidacy for a fifth term as president.
The mass protests led the army, Algeria's ultimate power brokers, to abandon Bouteflika and he stepped down. However, the protests continued with demonstrators demanding a more thorough overhaul of the ruling elite, an end to corruption and for the army to quit politics.
Although the security forces have not moved to quash the protests with force, international rights groups have accused them of attempting to suppress the movement using a wave of arrests.
President Abdelmadjid Tebboune, elected in a vote boycotted by the protest movement, has praised the demonstrations as a moment of national renewal, but has also sought to end them.
Official campaigning starts next week for parliamentary elections, which the protest movement also looks set to boycott and which Tebboune hopes will help him turn a page on the unrest.
(Reporting by Hamid Ould Ahmed and Lamine Chikhi, writing by Angus McDowall, editing by Nick Macfie)
