Reports that a Hong Kong pro-democracy protester was beaten in the grounds of the Chinese consulate in Manchester have sparked outrage.

Tory MP Iain Duncan-Smith and shadow foreign secretary David Lammy called for the Chinese ambassador to be forced to explain what happened after the confrontation on Sunday.

Downing Street said the reports were “extremely concerning”, while Mayor of Greater Manchester Andy Burnham said it is “never acceptable” for a protester to be assaulted.

Scuffles broke out outside the building in Manchester at around 3pm, with footage posted on social media apparently showing one protester being beaten inside the consulate grounds.

The campaigner told BBC Chinese that staff from the building had ripped down pro-democracy posters before he was beaten.

“They dragged me inside, they beat me up,” he said, adding that he was then pulled out by UK police.

“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).”

According to the Crown Prosecution Service, UK police are not allowed to enter consular grounds without permission.

A spokesman for Greater Manchester Police said: “Greater Manchester Police are aware of an incident that took place at around 3pm on Sunday October 16 at the Chinese consulate in Manchester.

“Officers were present and responded immediately to defuse the situation. Inquiries are ongoing at this time to understand the full circumstances.

“A police patrol plan is in place in the area following this incident.”

Sir Iain called for the Chinese ambassador to the UK to be made to apologise, and those responsible sent back to China.

Mr Lammy said: “The Foreign Secretary should urgently summon the Chinese ambassador to demand an explanation for the incident.

“The UK stands for freedom, the rule of law and democracy. The quashing of peaceful protest will never be tolerated on our streets.”

Mr Burnham said: “What took place yesterday outside the Chinese Consulate in Manchester was deeply worrying and has no place in a city region like ours that prides itself on peoples’ right to protest peacefully.

“Greater Manchester Police immediately started a full investigation and are in close touch with the Home Office and Foreign Office.

“It is important that the full facts surrounding this incident are established and for that we will need to wait for the investigation to conclude.

“However, on the basis of what I have seen, I want to make clear that it is never acceptable for peaceful protestors to be assaulted and those responsible need to be held to account for their actions.”