Riot police swiftly detained dozens at a protest march in Belarus on Sunday after strongman leader Alexander Lukashenko raised hopes for change by meeting jailed opposition figures.

Large numbers of black-clad masked police, internal troops and men in plainclothes emerged from unmarked minibuses and ran towards protesters in the capital Minsk, pulling some to the ground, witness footage on independent news sites showed.

The Viasna rights group, which monitors detentions at political protests, said at least 39 people had been detained in Minsk as well as around a dozen in other cities.

Among those detained were journalists from Russia's TASS state news agency, although they were later released, the agency reported.

Protesters have gathered every weekend since Lukashenko claimed victory in August 9 elections over a popular opposition candidate, Svetlana Tikhanovskaya, who claims to have been the true winner.

The European Union and the United States have refused to recognise Lukashenko's inauguration for a sixth term, saying the polls were not free and fair and condemning alleged abuse and torture of detained protesters.

The United States and the EU have hit Belarus with sanctions for allegedly rigging the vote and orchestrating the crackdown on protesters, targeting key officials -- but not Lukashenko himself.

The Viasna rights group said at least 39 people had been detained in Minsk as well as around a dozen in other cities 
The Viasna rights group said at least 39 people had been detained in Minsk as well as around a dozen in other cities  AFP / -

Protesters came out with umbrellas on a rainy afternoon for the latest in a series of mass protests urging Lukashenko to step down, called the "March of Pride".

It came after the 66-year-old authoritarian leader, in power since 1994, on Saturday took the unusual step of visiting a group of recently jailed opposition politicians, officially to discuss his plans for constitutional reforms.

The opposition hailed this as a sign that Lukashenko senses his weakness and is seeking some compromise with the protest movement.

However the authorities on Sunday ordered a reduction of mobile internet service and sent military vehicles into the centre of the capital Minsk.

Several thousand protesters dodged police who closed off main streets to prevent the columns of marchers from reaching the city centre.

Police used stun grenades and water cannon, spraying plain and coloured water at demonstrators.

Some of those detained were wrapped in the red-and-white protest flag, footage posted by the Tut.by news site showed.

One man had his head bandaged at the scene, the Belsat news site reported.

Russia