— After a fresh outbreak of violence between Hong Kong police and pro-democracy demonstrators, a Hong Kong court granted an injunction Monday that could set in motion a bid by authorities to clear parts of the main protest site.

The court action spelled out some limits, such as requiring security forces to give notice before moving against the protest encampment. But it reflects expanding efforts by officials to sweep away visible signs of the most serious challenge to Beijing’s control since it took over the former British colony.

The protests, which began more than two months ago over election rules imposed by Beijing, have shown resilience despite steady crackdowns and pressures.

But after an attempt to surround government headquarters late Sunday night was thwarted by riot police armed with pepper spray, batons and water hoses, a split among those at the main protest site in the Admiralty area was evident. Some accused student leaders of lacking a firm plan before trying to expand their occupation.

At least 58 people, including 11 police officers, were injured during the clashes Sunday night and Monday morning, according to Hong Kong’s Hospital Authority. At least 40 protesters were arrested, authorities said.

Student leader Alex Chow apologized to his fellow demonstrators, acknowledging that protest leaders should have been better prepared. But he blamed the injuries and violence on the police, insisting that the protesters had remained peaceful.

Now, the next steps on both sides are unclear.

Chow and other student leaders said they wanted to consult others in the pro-democracy movement on their future course of action.

Meanwhile, three protesters, including student leader Joshua Wong, announced that they were beginning a hunger strike intended to last until the government resumes a dialogue with demonstrators about their demands.

Hong Kong’s embattled chief executive, Leung Chun-ying, told reporters Monday that police had so far been tolerant but would now “enforce the law without hesitation” to end the protests, which have paralyzed parts of the Asian financial hub.

He called the protesters’ actions “not only illegal” but also “in vain.”

“Some people have mistaken the police’s tolerance for weakness,” Leung said.

The court injunction covers some parts of the main protest site.

The protesters are calling for free elections in 2017 for Hong Kong’s next chief executive, rather than a choice among Beijing’s pre-screened candidates.

Hong Kong’s pro-democracy movement represents the biggest challenge to Beijing’s authority since the territory reverted to Chinese rule in 1997. At the time, Hong Kong was incorporated under a “one country, two systems” formula that gives the territory some independence from China, with a promise of full democracy later.

The latest clashes came just after British lawmakers said they were told they would not be allowed to enter Hong Kong as part of a government inquiry into the status of the former colony and its progress toward democracy.

Chinese Foreign Ministry spokeswoman Hua Chunying said Beijing told Britain that it opposes the inquiry and reserves the right to decide whom to let into the city.

Meanwhile, U.S. officials urged restraint. “We encourage differences between Hong Kong authorities and protesters to be addressed peacefully through dialogue,” said State Department spokeswoman Jen Psaki.

The Hong Kong protests had drawn tens of thousands daily since beginning in late September. But in recent weeks, the numbers of protesters staying overnight in the encampments have dwindled to hundreds as public support has waned.

Deane reported from London. Kris Cheng Lok-chit in Hong Kong contributed to this report.