A spokesman said people had "illegally entered" the grounds and any country's diplomats would have taken "necessary measures" to protect their premises, the BBC reported.

On Tuesday, Hong Kong leader John Lee weighed in on the event, saying it should be dealt with in accordance with local laws.

Police are investigating an assault on the pro-democracy protester on Sunday. Footage shows men emerging from the consulate and dragging a man inside.

The violence has prompted loud calls for the UK government to summon China's ambassador, and possibly take further action.

The protester, identified as Bob, suffered several physical injuries and spent a night in hospital for treatment.

However, China is sticking to a different version of events from the police.

"People [who] intended to cause nuisance entered the Chinese Consulate-General in Manchester illegally... threatening the safety of a Chinese diplomatic facility," said foreign ministry spokesman Wang Wenbin at a daily press briefing in Beijing.

He added that any attempt to infringe on the consulate's "tranquillity and dignity" would "not be tolerated".

According to a statement by the Greater Manchester Police, around 30 to 40 people had gathered outside the consulate and patrols were in the area to help maintain the "peaceful protest".

"Shortly before 4pm a small group of men came out of the building and a man was dragged into the consulate grounds and assaulted," a police statement said.

"Due to our fears for the safety of the man, officers intervened and removed the victim from the consulate grounds."

The consulate says protesters had displayed an insulting portrait of China's president.

Bob told BBC Chinese that "mainlanders" - people from mainland China, as opposed to Hong Kong - had come out of the consulate and destroyed their posters.

"As we tried to stop them, they dragged me inside, they beat me up," he said. "It's ridiculous. They [the attackers] shouldn't have done that. We are supposed to have freedom to say whatever we want here [in the UK]."

The protest took place on the same day China kicked off its twice-a-decade Communist Party Congress, where its leader President Xi Jinping is widely expected to secure a third term in power.

Xi had on Sunday made reference to the situation in Hong Kong, saying Beijing had turned the situation in the city from "chaos to governance".

Beijing imposed a sweeping national security law on the former British colony after pro-democracy demonstrations in 2019.

(With UNI inputs)