Several dozen activists gathered on a central square in Minsk, holding up the photos of those detained.
Five minutes after the protest started, law enforcement officers encircled the demonstrators and ejected them from the square, injuring at least one.
"They kicked me in the stomach and I almost fainted," said Anatoly Lebedko, leader of the United Civil Party.
Belarusian security officers have detained three people as part of the investigation into a July 3 explosion in Minsk.
A blast rocked Minsk on July 3 during an open air concert as part of the country's Independence Day celebrations. The event was attended by President Alexander Lukashenko. Over 50 people were injured in the blast, which was caused by a homemade device.
The Interior Ministry has declined to comment on the arrests, saying it has the right to detain a suspect for a period of up to three days.
Authorities in the ex-Soviet state have come under severe international criticism for their clampdown on dissent, and Lukashenko is currently barred, along with other senior Belarus officials, from entering the United States and the European Union.