India's opposition The Bharatiya Janata Party (BJP) has called for a shutdown in the southern state of Andhra Pradesh, whose capital Hyderabad was subject to a terrorist attack Thursday which killed at least 14 and injured more than 110.

The BJP said in the statement that all people to voluntarily observe the shutdown to protest the blast and show their sympathies with the victims' families.

It also blamed the state government of failing to take steps to prevent the blasts despite warnings from the central intelligence agencies that terrorists were ready to strike in the city.

Police have stepped up security in the city and other major towns in view of the shutdown call and Friday prayers of Muslims, according to local media reports.

Indian Home Minister Sushikumar Shinde visited the site of the twin blasts in downtown Hyderabad Friday and promised the government would leave no stone unturned in its investigation.

But he refused to speculate on the perpetrator of the attack, saying because the Indian Parliament is now in session.

Local media said the major suspect in the blasts was the militant group Indian Mudjahideen which was suspected to be behind a series of terrorist attacks.