JAIPUR, India - At least 45 people were killed and 100 wounded Tuesday in string of bomb blasts in this ancient city in western India that is known as a popular tourist destination, police and hospital officials said.

The explosions took place in markets and several other areas of the Jaipur, capital of Rajasthan, a region dotted with palaces and temples that draw hundreds of thousands of Indian and foreign tourists every year.

N.S. Shekhawat, superintendent of the Sawai Man Singh hospital in Jaipur, where most of the bodies were taken, confirmed that at least 45 people had been killed.

Another 100 people were wounded in Tuesday's attacks, police said.

A.S. Gill, a top police official, said six explosions took place in markets and several other areas of the historic city.

A seventh bomb was defused before it exploded, Gill said.

"Obviously, it's a terrorist plot," Gill told reporters. "The way it has been done, the attempt was to cause the maximum damage to human life."

Bicycles were believed to have been used in the bombings, but Gill did not say if any of the explosives were detonated by suicide bombers riding through crowds or if all the bombs were on parked bicycles.

New Delhi, India's capital, and Mumbai, the country's financial centre formerly known as Bombay, were among several cities put on high alert shortly after the bombings, which began just before 7:30 p.m.

Security was also stepped up at airports and railway stations across the country, said India's junior home minister, Sriprakash Jaiswal.

One the blasts in Jaipur reportedly hit a market near a temple dedicated to the Hindu monkey god Hanuman.

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

The Press Trust of India news agency said another blast occurred near the Johari Bazaar - the city's jewelry market, a popular destination for tourists.

The tourist season ended in March and there were no immediate indications that foreigners had been caught in any of the blasts.

Bombings have plagued India since 2005. Last year, two explosions killed 43 people in the southern city of Hyderabad; seven bombings along Mumbai's commuter rail network killed nearly 200 people in July 2006, and three New Delhi markets were bombed in October 2005, killing 62 people.

There have also been a number of smaller attacks.

India has repeatedly blamed the attacks on Islamic militant groups backed by neighbour and rival Pakistan - an allegation Islamabad routinely denies.

While Indian officials did not openly blame Pakistan-based militants for Tuesday's attack, Jaiswal suggested the bombings were connected to previous explosions.

"The blasts are part of a big conspiracy," he told reporters.