Political parties of various hues on Monday strongly attacked the UPA government over its "failure" to curb violence against north Indians in Maharashtra by Maharashtra Navnirman Sena (MNS) cadres.

RJD chief Lalu Prasad, Samajwadi Party leader Amar Singh, CPI(M) Politburo member Brinda Karat and BJP's Shahnawaz Hussain unequivocally condemned the UPA government as well as the Congress-led Maharashtra government, for the attacks on north Indians.

Prasad, while strongly condemning attacks on north Indians in Maharashtra, especially Sunday's incident of MNS activists beating up Railway Board examinees in Mumbai, said,

"It is the failure of the state government that it has not been able to curb attacks on north Indians there. I strongly condemn the violence and 'awaragardi' (hooliganism) by MNS cadres against north Indians and students in the state".

Speaking to reporters outside Parliament, he said he will raise the issue when Lok Sabha meets again later in the day. Samajwadi Party general secretary Amar Singh also joined the Opposition parties in criticising the attacks.

Singh said Sunday's incident "was the most deplorable act by MNS activists". He said the Chief Minister and Deputy Chief Minister of the state have proved to be "useless" in preventing attacks on north Indians.

On a sarcastic note, Singh expressed his gratitude to Shiv Sena chief Bal Thackeray for criticising him on his opposition to incidents of violence against north Indians.

"I am honoured that a veteran leader like Bal Thackeray chose to criticise me. This shows that he finds SP a challenge in Maharashtra," the SP leader said.

"It is the responsibility of the UPA government to protect north Indians in Maharashtra, but it has failed to do so. The Congress will have to pay for this," BJP leader Shahnawaz Hussain told reporters outside Parliament. CPI(M) leader Brinda Karat also echoed the sentiments of other party leaders and called the attacks on north Indians in the state as "unconstitutional".

"The Congress-NCP led state government is empowering MNS and it is the responsibility of the Centre as well as the state government to stop the continuous attacks on north Indians in Maharashtra," she said.

Describing MNS chief Raj Thackeray as a goonda, JD(U) chief Sharad Yadav said he should be booked under various sections of the IPC for disturbing amity in Maharashtra.

"The UPA government is morally responsible for ensuring law and order all over the country. The Congress-led government is ruling Maharashtra and therefore it should have ensured safety of the common man against such attacks by lumpen elements," Yadav said.

SP Parliamentary Party leader Ram Gopal Yadav described the Maharashtra government as "useless, irresponsible and impotent", and said all these incidents are taking place because of its "inactivity".

RJD leader Devendra Prasad Yadav said the situation in Maharashtra "was fit for use of Article 355".