Centre has asked all states to be extra vigilant against attempts by terrorists and subversive elements during the festive season.<br/><br/>Acting on intelligence inputs, the Home Ministry has issued a nation-wide advisory asking states to deploy additional forces at public places and religious sites to foil any untoward incident. <br/><br/>Sources said the police of metro cities including Delhi, Mumbai, Kolkata, Chennai, Bengaluru and Hyderabad have been specially asked to be extra vigilant. <br/><br/>The states have also been asked to be alert during the<br/>festivals over the provocative sloganeering, especially near religious places.