NEW DELHI -- Five blasts in heavily-populated market areas and near a subway station around India's capital in less than an hour Saturday evening killed at least 15 people and injured more than 80, capping a summer of attacks around the nation targeted at economic areas.

Indian Mujahideen, an Islamic extremist group, claimed responsibility for the attacks in an email to Indian media outlets. The blasts had hallmarks of recent attacks in the city of Ahmedabad in the western state of Gujarat in July that killed 53 and in the tourist city of Jaipur in Rajasthan in May that killed more than 60. A series of blasts in the high-technology capital of Bangalore in July also killed one.

The Delhi blasts were triggered at a popular shopping hour early evening Saturday, a working day in Delhi. Police defused two other live bombs, one at a cinema and one in a children's park near India Gate, the monument in the heart of the city on New Delhi's equivalent of the National Mall in Washington and a popular spot for an evening excursion for families.

Police say Indian Mujahideen is a front for the Students Islamic Movement of India -- a terrorist group banned by the Indian government since 2001. In previous emails, Indian Mujahideen had warned that Delhi would be a target. Shahbaz Hussain, a senior SIMI leader when the group was banned in 2001, was arrested Aug. 25. A 32-year-old cyber-cafe owner in Lucknow, Uttar Pradesh, police say he is the sender of past emails attributed to Indian Mujahideen. Rajasthan police say he also was the mastermind of the Jaipur attacks. Indian Mujahideen also sent an email before the Ahmedabad blasts claiming the group's responsibility.

Among the five blasts in New Delhi, one was in Karol Bagh near the city center's commercial district; two were around Connaught Place, a shopping area in the center of the city popular with tourists and locals alike; two were in the popular middle-class M Block Market in Greater Kailash 1, a tony residential district in South Delhi. One eyewitness near one of the Connaught Place attacks said there was a loud blast followed by people running in panic. The area is heavily policed and officers were on the scene in two minutes. They ordered local stores shuttered.