At least 60 people have been killed and 150 others wounded in seven bomb blasts that ripped through crowded areas of a city in western India.

Police officials in Jaipur said the explosions took place in markets and several other areas of the historic city in Rajasthan state.

The region is dotted with palaces and ancient cities that draw hundreds of thousands of Indian and foreign tourists every year.

Rajasthan's police chief, AS Gill, told local media that the blasts were "obviously a terror attack".

He added bicycles may have been used in the bombings. However, he did not say if the explosives were detonated by suicide bombers riding through the crowds or if the bombs had simply been planted on parked bicycles.

The first blast took place at 7.25pm local time (1.55pm GMT), police said. Another reportedly hit a market near a temple dedicated to the Hindu monkey god Hanuman.

Tuesdays are the day of worship set aside for Hanuman, and the temple was packed with people offering prayers on the way home from work.

Officers said another blast took place near the Johari Bazaar - the city's jewellry market, a popular destination for tourists. An eight bomb was found and defused by police.

However, the tourist season ended in March and there were no immediate indications that foreigners had been caught in the explosions.

Shortly after the bombings, authorities put New Delhi, India's capital, and Mumbai, the country's financial centre, on high alert along with several other cities. Security was also stepped up at aiports and railway stations across the country.