The Punjab Police has detained several radical Sikh leaders ahead of the 32nd anniversary of 'Operation Bluestar', the Army's action on Amritsar's Golden Temple complex in June 1984 to flush out armed extremists, police officials said on Saturday.The detention of the hardliners leaders has been done as a preventive measure ahead of the Bluestar anniversary on (Monday) June 6.Most of the radical leaders have been taken into custody in the past 24 hours, a senior police officer told IANS here.In Ludhiana, hardliner Sikh leaders Daljit Singh Bittu, Manvinder Singh Giaspura and Jaswant Singh Cheema were detained.Radical leader Dhian Singh Mand, who was last year appointed as interim jathedar (chief) of the Akal Takht by Sikh hardliners at a congregation near Amritsar, was also taken into custody by Amritsar police on Thursday.Mand was detained to prevent him from reaching the Akal Takht, which is situated inside the Golden Temple complex, to address people during functions to mark the Operation Bluestar anniversary.In Bathinda, the police detained hardline leader Gurdip Singh and Hardeep Mehraj.Radical Sikh organization Dal Khalsa has called for an 'Amritsar Bandh' on Monday.