Hong Kong on Saturday reported 27,647 new coronavirus cases while Shanghai closed schools and parks and authorities in Beijing suspended access to a residential area and told the public not to leave the capital after new infections were found.

Hong Kong leader Carrie Lam warned the territory’s wave of infections may not have peaked despite stringent controls on travel and business.

“At this moment, we could not comfortably say that we have passed the peak,” Lam said at a news conference. “We’d rather take a very cautious stance.”

On the mainland, the government reported 588 new confirmed cases and no death in the 24 hours through midnight Friday. Its numbers are low compared with some countries, but authorities say they are ready to lock down communities if one case is found.