Radical preacher Amritpal Singh's supporters, some of them brandishing swords and guns, broke though barricades and stormed into a police station complex here on Thursday, camping there till they were "assured" that an arrested man would be released.
Three policemen were hurt during the clash, officials said.
A large police force kept watch but refrained from taking any action as the preacher, often described as a Khalistan sympathiser, and other protesters stayed put at the Ajnala police station for hours.
Amritsar Police did not immediately make it clear whether any case had been registered against Amritpal Singh or his supporters over Thursday's violence.
Earlier, they staged a protest in the middle of the road at Dhilwan toll plaza in Kapurthala district when they were stopped by police from marching towards Amritsar.
Dubai-returned Amritpal Singh, who heads an organisation called 'Waris Punjab De', talked to reporters at the police station, issuing an "ultimatum" for the release of his supporter Toofan Singh.
The preacher reportedly issued a threat to Union Home Minister Amit Shah recently, saying he will meet the same fate as that of former prime minister Indira Gandhi.
A case was registered against Amritpal Singh and his 30 supporters for allegedly kidnapping and thrashing Barinder Singh, a resident of Chamkaur Sahib in Rupnagar district.
Barinder Singh, in his complaint, had told police that Amritpal Singh's associates had abducted him from Ajnala and took him to an unknown place where he was brutally thrashed.
Before reaching Ajnala, Amritpal Singh and his supporters staged a protest at Dhilwan toll plaza after being stopped by police to march towards Amritsar.
But the police later allowed them to continue with their march towards the Ajnala police station.
Their protest led to a traffic jam on the Amritsar-Delhi national highway for some time.
Amritpal Singh and his supporters were prevented by police at the Ajnala bus stand by erecting barricades. However, his supporters forced their way through the barricades and also managed to gain entry inside the police station after clashing with police.
Stones were also hurled in the incident.
The protesters asked the police to cancel the FIR and also threatened that they would not leave the police station till Toofan Singh was released.
Amritpal Singh and his supporters had also brought a vehicle carrying a copy of the "Guru Granth Sahib" for holding 'Amrit Sanchar' (a Sikh ceremony) at the police station.
Senior police officials also reached the police station and held a meeting with Amritpal Singh and his supporters.
Amritsar (Rural) Senior Superintendent of Police Satinder Singh said a special investigation team has been formed and added that the arrested person will be released on Friday.
Carrying swords and guns, scores of supporters led by Amritpal Singh had assembled at the police station.
Amritpal Singh told the media that police assured him that Toofan Singh would be released on Friday, following which they agreed to lift the 'dharna' at the police station.
However, he said they would remain in Ajnala till Friday morning unless the arrested Sikh was released by the police.
Amritpal Singh is the head of 'Waris Punjab De' -- an organisation founded by actor and activist Deep Sidhu who died in a road accident in February last year.
