The Akali Dal said the crackdown was aimed at defaming Sikhs.
Calling the Punjab Police's massive manhunt for Khalistani leader Amritpal Singh "extra-constitutional" and a "conspiracy", opposition party Shiromani Akali Dal on Wednesday offered legal aid to those arrested in the crackdown.
"Shiromani Akali Dal has decided to provide complete legal assistance to all Sikh youth arrested in the ongoing extra-constitutional crackdown in Punjab and ensure their rights are not trampled upon by AAP Punjab," Akali Dal leader Sukhbir Singh Badal wrote on Twitter.
The conservative party, which counts the top religious body of Sikhs as its ideological mentor, has also released a list of helpline numbers for coordinating the effort.
In another tweet, Mr Badal said, "Shiromani Akali Dal strongly condemns the indiscriminate arrests of innocent Sikh youth, especially the Amritdhari youth on mere suspicion through resort to extra-constitutional methods. We demand the immediate release of all innocents arrested in the ongoing crackdown".
"Shiromani Akali Dal stands for Justice and the protection of the rights of the Punjabis in general and the Sikhs in particular within the federal framework, with more powers to the states, a demand echoed now by other political parties too," he tweeted.
Mr Badal also stated that with these arrests, the state's Aam Aadmi Party (AAP) government is trying to defame the Sikh community to polarise voters and gain electoral ground.
"SAD strongly condemns the puppet AAP regime in Punjab for the undeclared emergency and reign of repression and terror let loose in the state. We warn the government against dangerous conspiracies to defame the most patriotic Sikh community for communal polarisation and electoral gains," Mr Badal said.
More than 150 people have been arrested in Punjab for "disturbing peace and harmony" in the state, the police said on Tuesday, as they continued to search for Amritpal Singh, a supporter of the call for Khalistan, a separate nation for Sikhs.
The police also arrested four more people for allegedly helping Singh escape on Saturday and released seven photographs of the self-styled preacher, including some in which he is not wearing a turban, to seek public help to catch the fugitive.