In a crackdown against Shiv Sena, over 1000 of its activists have been detained ahead of the release of Shah Rukh Khan starrer 'My Name is Khan' after the party stepped up its protest against the film over the actor's remarks favouring inclusion of Pakistani cricketers in IPL.

"In the last 24 hours, a total of 1,023 Sainiks have been arrested. While 955 were picked up under the preventive action, the rest were put behind bars for different cases, including for protesting outside the theatre, vandalising screens among others," police said.

Tight security has been provided to 63 theatres across the city where the movie is scheduled to be released on February 12, they said.

Guidelines have also been issued to all police stations by the city police chief regarding security arrangements.

The Sena has renewed its threat not to allow the release of "My Name is Khan".