Security was beefed up on Tuesday at the residence of Maharashtra Navnirman Sena chief Raj Thackeray and all entrances barricaded ahead of his possible arrest after a case was registered against him for making provocative statements against north Indians.

Media personnel trying to reach Thackeray's residence were told to wait several meters away.

A senior police official had on Monday said that Thackeray and Samajwadi Party leader Abu Asim Azmi will be arrested for making provocative statements, which resulted in incidents of violence across the city last week.

"The cases have been registered on the basis of certain evidence and arrest is mandatory," Joint Commissioner of Police (Law and Order) K L Prasad said on Monday.

However, Prasad had refused to disclose when the arrests would be made and said the charges under which Thackeray and Azmi had been booked were non-bailable and cognisable.

The city police had registered cases on Sunday night against Thackeray and Azmi at separate police stations under sections 153 (wantonly giving provocation with intent to cause riot), 153 A (promoting enmity between groups on the basis of place of birth, residence, etc), 153 B (assertions prejudicial to national integration) and 117 (abetting the commission of an offence by the public), he said.

Incidents of violence in the city, specifically targeting north Indians, began on February 3 after Thackeray launched a verbal assault against the community.

The case had been filed against Thackeray at the Vikhroli police station on account of a speech made by the MNS chief in the suburb ahead of SP rally on February 3, Prasad said.

Azmi allegedly made provocative speeches at the SP rally on February 3 at Shivaji Park in central Mumbai.