Leading Hong Kong democracy activist Joshua Wong was arrested Friday, his party said, a day ahead of a planned rally in the city that has been banned by police.

“Our secretary-general @joshuawongcf was just arrested this morning at roughly 7:30,” Demosisto tweeted. “He was forcefully pushed into a private minivan on the street in broad daylight. Our lawyers following the case now.”

BREAKING: Our secretary-general @joshuawongcf was just arrested this morning at roughly 7:30, when he was walking to the South Horizons MTR station. He was forcefully pushed into a private minivan on the street in broad daylight. Our lawyers following the case now.

— Demosistō 香港眾志 (@demosisto) August 30, 2019

Hong Kong has been wracked by three months of political unrest, with huge, peaceful demonstrations interspersed by violence that has seen stand-offs between police and protesters.

Saturday marks the fifth anniversary of Beijing’s rejection of a call for universal suffrage in the city, a decision that sparked the 79-day Umbrella Movement led by mainly young protesters including Wong.

Permission for a mass rally this weekend was denied on security grounds, raising the likelihood of another weekend of clashes between police and protesters, who will likely come out in defiance of the ban.

In a letter to the rally organisers the Civil Human Rights Front (CHRF), police said they feared some participants would commit “violent and destructive acts”.

The protests ignited when the city’s Beijing-backed government tried to pass a bill allowing extraditions to mainland China.

But they have evolved into a wider call for greater democracy and an investigation into allegations of police brutality.

Protesters say freedoms in the semi-autonomous city, unique within China, are being eroded by Beijing.

More than 850 people have been arrested in connection with the recent protests since June.