Police sounded high alert in Hyderabad and other cities in Andhra Pradesh after two blasts killed over 10 people in Hyderabad and injured scores of others.
Police with dog squads began search operations in several busy market areas in Hyderabad and its twin city Secunderabad to foil any explosives.
Security was beefed up at Rajiv Gandhi International Airport at Shamshabad, state secretariat, Charminar and other vital installations, a police official said.
An alert was also sounded in coastal city of Visakhapatnam, temple town of Tirupati and other major towns across the state.
