Belarus strongman faces mass protests after jailing of his main rivals

Riot police officers watch opposition supporters in Minsk on June 19.

(CNN)Mass protests are spreading across Belarus as opposition to the reelection campaign of President Alexander Lukashenko grows, local media and human-rights organizations have reported.

Lukashenko has ruled the former Soviet republic of more than 9 million people since 1994 and is running for the sixth time in an election scheduled for August 9. He has long drawn international criticism for suppressing dissent, and the country's secret police -- still known as the KGB -- often detain and harass opposition activists and independent journalists.
Demonstrations on Friday, in which thousands marched on the streets of 10 cities, were prompted by a series of arrests, in what the opposition activists called an attempt to take popular candidates out of the presidential race. Two of Lukashenko's main opponents are currently in KGB and police detention: popular YouTube blogger Sergei Tikhanovskiy, who was detained in late May, and former Belgazprombank chairman Viktor Babaryko, who was arrested on June 18 along with his son and campaign manager, Eduard Babaryko, according to their campaigns.
    Belarus presidential candidate Viktor Babaryko holds a press conference in Minsk on June 11.
    Following the news of the latest arrest, activists started forming "human chains of solidarity," some of which stretched from to several kilometers, according to the organizers and local media reports.
    The independent non-governmental organization Viasna, which monitors protest activity in Belarus, reported Saturday that at least 120 people were detained overnight, including many journalists.
    On Friday, Lukashenko said the protests are a foreign plot and claimed that the country's law enforcement "thwarted a Maidan," alluding to the 2014 revolution in Ukraine that ousted the country's pro-Russian president.
    "We managed to take some steps ahead of schedule and quash the large-scale plan to destabilize Belarus," Lukashenko said ac