The Belarusian rights group Vyasna says 150 people have been detained in connection with the protests, though some of them have been released.
Milinkevich was addressing a crowd of a few thousand on the evening of March 22 that had dwindled to about 200 by this morning. Evening rallies since the March 19 election have drawn several thousand people to Minsk's Kastrychnitskaya (October) Square each night.
The opposition, backed by much of the international community, alleges the election was neither free nor fair and that a new vote should be held.
Official results say Lukashenka defeated Milinkevich, 82.6 percent to 6 percent.
(compiled from agency reports)
MEET THE CANDIDATES: Read brief biographies of the four candidates in the March 19 election.