New Delhi (PTI): Strongly condemning the attack on railway examination centres in Mumbai by MNS activists, Left parties on Monday termed it as a "blatant" assault on the Constitution and demanded immediate arrest of Raj Thackeray, saying any leniency shown to "divisive forces" will have far-reaching consequences.

In a statement, the CPI(M) Polit Bureau said the attack was a "blatant" assault on the Constitution which the Maharashtra government is duty bound to protect and take stringent action against the perpetrators of such crimes.

"That it has failed to do so and in fact showing leniency to the leader of the outfit shows the utter bankruptcy of the politics of Congress and its coalition partner," the CPI(M) said.

The CPI said such attacks should not be tolerated and Thackeray and his supporters must be "immediately arrested and prosecuted".

"Any leniency shown to these divisive forces will have far-reaching consequences to the unity and integrity of the country," a party statement said.

The CPI(M) said the attack was "pre-planned" and part of the "continued parochial and divisive" campaign launched by the MNS.

"The failure of police and intelligence units to prevent the incident is quite obvious," the statement claimed.

The MNS had attacked 13 railway board examination centres in suburban Mumbai in protest against "inadequate representation" of locals and chased away candidates from north India.