The 30-year-old has been on the run since Saturday and over the weekend his supporters staged protests in the majority Sikh state.

The Punjab Police India Twitter account states that 112 people have been arrested so far.

They also said a vehicle allegedly used by Singh and abandoned during a police chase in a rural area of Jalandhar had been seized.

The search for Singh is having a widespread impact on the whole state with the Times of India and CNN reporting that authorities have blocked internet access for a third day.

Police reportedly justified the shutdown by saying it was to keep the peace and prevent the spread of fake news.

The Khalistan movement is banned in India, where officials see it and affiliated groups as a national security threat.

But the movement still has some support in the state, as well as in countries with a sizeable Sikh diaspora such as Canada and the UK.

Many Sikh organisations have expressed concern and denied that Amritpal Singh is a fugitive, claiming there are online videos showing his arrest.

Sikh Federation UK told Sky News there are fears he has been killed or that his extrajudicial murder is being planned.

The crackdown comes after Singh's supporters stormed a police station in February, demanding the release of an aide who had been arrested.

Several police officers were injured and police vehicles were damaged.

On Sunday a man was arrested on suspicion of violent disorder after a crowd incident saw windows smashed at the Indian High Commission in London.

Footage posted on social media showed a man detach the Indian flag from the first-floor balcony of the building while a crowd of people below waving bright yellow "Khalistan" banners appeared to encourage him.

They are believed to be supporters of the Sikh separatist movement but UK foreign office minister Tariq Ahmad said he was "appalled" by the incident.

"This is a completely unacceptable action against the integrity of the Mission and its staff," he wrote on Twitter. "The UK government will always take the security of the Indian High Commission seriously."