The Home Ministry specifically asked authorities in Delhi, Mumbai, Nagpur, Pune, Hyderabad, Bangalore, Ahmedabad, Kolkata, Chennai and Vadodara to remain alert against any communal tension.
In an advisory, the ministry said that the country has recently witnessed communal incidents in many places during the festivals of Ganesh Chaturthi and Durga Puja.
It also said that communal atmosphere was strained in some states during Bakrid over issues related to animal sacrifice. Since the Diwali/Kali puja will be celebrated on October 23 and would attract huge crowd, issues like bursting of fire crackers, use of loud speakers, raising of provocative slogans by members of one community, forcible collection of donations, installation of idols at disputed places, acts of misbehaviour and eve teasing could lead to communal tension, it said.
"It is necessary that continued vigil and proper security arrangements are made at places of worship during observance of the festival especially in the communally hyper sensitive/sensitive areas to prevent communal disturbances," it said, adding, adequate crowd control must be made at venues of mandaps/pandals and places of congregation. The advisory also stressed on the need for vigil on cyber space to keep in check provocative material.