The CBI on Monday launched parallel raids and detained TMC heavyweights and ministers Firhad Hakim, Subrata Mukherjee and MLA Madan Mitra in its probe on the Narada sting case. Within hours, Chief Minister Mamata Banerjee reached the CBI office. CM Mamata Banerjee has challenged the CBI to arrest her as well while calling the detention of her ministers 'illegal'.