An activist of Alternative, Illia Dabratvor, was released after 14 days in custody.
Yulia Stepanova, an activist of the civil campaign European Belarus, wrote it on Facebook.
As charter97.org has learnt, friends and journalists came to meet the activist outside the detention centre.
The activist was sentenced to 14 days in custody on July 29. His friends think he was arrested for hanging out a banned national white-red-white flag in Dziarzhynsk ahead of the Day of Independence Restoration.