New Delhi  - A live bomb was found in the western Indian city of Surat Wednesday, bringing the number of unexploded bombs found there over two days to 19, police said.

The explosive was found in a busy market area a short distance from a site visited by Narendra Modi, chief minister of Gujarat state, four days after 21 bombs exploded in Ahmedabad, the state's principal city, killing at least 50 people and injuring 200.

Modi, who visited five Surat sites where bombs were discovered Tuesday, said terrorists were waging a "proxy war" against India.

The same rules should be applied as in war, the same atmosphere maintained, Modi said, "otherwise, terrorists will take advantage."

Schools, colleges, markets, malls, cinemas and public parks were closed in Surat Wednesday as a precautionary measure, police said. People have been asked to stay indoors as much as possible in the industrial city.

By targeting Ahmedabad and Surat, the terrorists were planning to cripple financial activity in Gujarat, Modi was quoted as saying by the PTI and IANS news agencies.

Gujarat is one of India's most industrially advanced states, and Ahmedabad and Surat are its industrial and commercial hubs.

The 19 bombs found in Surat were safely defused in and around the Varachha area, where several diamond-processing businesses are located. Two explosives-laden abandoned cars were also found and neutralized in the city Sunday.

The Ahmedabad blasts came a day after serial bombings in the southern city of Bangalore, India's information-technology hub, where one person died.

Modi said terrorists were targeting cities like Mumbai, Bangalore, Jaipur, Ahmedabad and Hyderabad with the intention of crippling financial activities in the country.

The chief minister asked people to remain alert but ignore rumours. He commended the people of Surat for their "remarkable alertness" that led to the discovery of the bombs and announced a reward of 21,000 rupees (about 495 dollars) for all those who had tipped the police.

Modi said anyone providing information about those behind the blasts would be rewarded with 5.1 million rupees and their identities would be kept secret.

Police said forensic evidence and e-mails sent by a group calling itself the Indian Mujahedin claiming responsibility for the blasts were being investigated.

All major cities in India, including the capital, New Delhi, remained on a high alert Wednesday with additional police patrolling roads and busy areas. (dpa)