The demonstrators, who provide police services in Algerian villages, were quickly surrounded by regular police despatched to the scene of the protest.

About 10,000 people took part in the demonstration, organisers said, and called on President Abdelaziz Bouteflika to bring their salaries and conditions in line with those of other security services. The demonstrators, most of them wearing their uniforms, chanted: "Bouteflika is the solution."

"We demand a rise in salaries and service indemnities along the lines of all the other security units," said Cherif Abdelkader, a community policeman from Chlef, 200 kilometres (124 miles) west of the capital.

"We only have the right to 21 days of leave a year. We take part in security sweeps without helmets or bullet-proof jackets," another said.