Seven pro-democracy lawmakers in Hong Kong have either been detained or face arrest on Saturday, in a move expected to escalate public fury after months of unrest.

A police statement said three of the lawmakers had been detained and charged Saturday with obstructing the local assembly during a raucous May 11 meeting over a now-shelved China extradition bill that sparked five months of protests calling for democratic reforms.

The others received summons to turn up at police stations Saturday to face arrest.

Pro-democracy lawmakers slammed the government clampdown as a calculated move to provoke more violence as an excuse to postpone or cancel Nov. 24 district elections — low-level polls viewed as a barometer of public sentiment in the semi-autonomous Chinese territory.

Anger has deepened against the police after Friday's death of a 22-year-old who fell off a parking garage after police fired tear gas during recent clashes.

"We'll say no to their plans," lawmaker Tanya Chan told a news conference. Referring to the upcoming vote, she said "it is a de facto referendum for all Hong Kong voters to cast their vote and say no to police brutality and say no to our unjust system. And this is definitely our chance to show our determination."

Watch: Hong Kong lawmakers clash over extradition law

Legislators clash over controversial amendments to extradition law. 0:48

She said the polls will send a crucial message also to Beijing, accused by protesters of interfering in the city's freedoms and rights promised when the former British colony returned to Chinese control in 1997.

Gary Fan, one of the lawmakers who received the police notice, said the arrest was a "dirty tactic" that is adding fuel to the fire.

"This is political suppression. People can see clearly that [Hong Kong leader] Carrie Lam continues to hide behind the police and is now using the legal system against the movement," he said.

Pro-democracy lawmaker Wu Chi-wai is restrained by security guards at the Legislative Council in Hong Kong in May 11. It is not yet known if Wu is among those detained or face arrest. (Vincent Yu/Associated Press)

The city's Constitutional and Mainland Affairs Secretary Patrick Nip denied the arrests were linked to the polls.

"There is no correlation between the two. The police are doing their job and investigating each and every case and take appropriate action," Nip said.

He said the government aims to conduct the polls smoothly and peacefully.

Violence erupts after vigils

Thousands attended multiple memorial events across the city Friday night, calling for truth and justice for Chow Tsz-Lok, the student who died Friday of injuries sustained in a fall.

Violence erupted later in familiar scenes that have beset the city with police firing tear gas to disperse hard-core protesters who set street fires, blocked roads and vandalized shops and public utilities. More protests are being planned this weekend.

Although the circumstances of Chow's fall have not been determined, many blamed police, who have been accused of heavy-handed tactics including widespread use of tear gas and pepper spray since the protests demanding democratic reforms started in June. His death will also complicate efforts by the government to cool down tensions.

There have been only few fatalities during the unrest, including some reported deaths by suicide and a man who fell to his death while hanging pro-democracy banners on a building.

More than 3,300 people have been arrested in the movement, that has since expanded to include calls for direct elections for the city's leaders and other demands.