A strike called by the main opposition Bharatiya Janata Party (BJP) in protest at Saturday's deadly explosions kept many people off work and shut schools in this mixed Hindu-Muslim city long troubled by ethnic tensions.
The BJP said the government — which has blamed foreign-based Islamic militants for the carnage — had not done enough to ensure security within India's borders.
"We have been constantly warning the Centre (government) that it should take adequate measures to strengthen internal security, but the Congress-led government has never bothered to rein in terror," said senior BJP leader Vijay Kumar Malhotra.
He accused the ruling coalition of a "soft approach on terrorism" after bombs ripped through a packed street eatery and an amusement park, where hundreds of people were watching a sound and light show.
Hyderabad, a normally teeming city of 6.5 million people and the capital of Andhra Pradesh state, was quiet early Monday, with about 2,500 state-run buses off the roads after 10 of them came under attack during the work stoppage.
State-run and private schools declared a holiday after the BJP called the state-wide strike.
Police fielded a flurry of anonymous calls Monday about possible bombs planted in Hyderabad, a high-tech hub where 11 people died in a blast at a mosque in May, and its twin city Secunderabad.
Bomb disposal teams and sniffer dogs fanned out to search the government secretariat which houses top ministries and offices, as well as a hotel.
At least one call turned out to be a false alarm after an unclaimed bag discovered at a private hospital was found to contain only clothes.
Forensic experts were Monday studying the material used in the bombs which were set off by timers and left more than 50 wounded.
"Yes, it is a timer-based explosive and one bomb that we defused, it also had a quartz clock timer," investigating officer Ram Mohan told the NDTV network.
Police recovered and defused one bomb found in a cinema a few hours after the twin blasts.
Initial reports said police had recovered several more unexploded bombs across the city, but this was later denied.
The state's chief minister, Y.S.
(Read content ‘Hindus say govt 'soft on terror' after blasts (AFP)’…)