Alexander Burakov had wanted to report on a trial of opposition politicians who had been accused of participating in "mass unrest", dpa news agency quoted Deutsche Welle as saying in a statement on Saturday. 

According to the statement, the freelance journalist was detained in the city of Mogilev, east of the capital Minsk, while he was waiting outside the courthouse with other media representatives. 

A court ruled that Burakov was guilty of "repeated participation in a non-authorised event", Deutsche Welle said. 

Burakov already spent 10 days in prison last year for his reporting. 

Deutsche Welle sharply criticized the sentence. 

Classifying a group of journalists outside a courthouse as a "forbidden event" was a further step by the regime under Alexander Lukashenko to suppress media reports, the broadcaster said. 

"We call on the authorities in Belarus to immediately suspend the sentence," said director Peter Limbourg. 

Burakov has gone on hunger strike to protest the sentence, Deutsche Welle said. 

During the hearing, he said he was tortured and treated inhumanely in custody. 

He was repeatedly woken up during the night and forced to strip naked. 

The human rights group Viasna said that two other journalists were also sentenced to prison for multiple days on Saturday. 

Since mass protests against the re-election of long-time ruler Lukashenko broke out last year, authorities have cracked down more and more on the media. 

At the peak of the demonstrations, hundreds of thousands of people protested against the election result, which is widely seen as having been rigged.