Indian Home Secretary G.K. Pillai told the media that "as of now, it appears it was a terror attack."
The following are major terrorist attacks in recent years in India.
Nov. 26-29, 2008:
Armed terrorists opened fire at eight different sites in a coordinated attack in Mumbai. They wielded automatic weapons and attacked locations including a train station, hotels, restaurants, a police station, and a hospital. At least 195 were killed and more than 300 wounded.
Oct. 30, 2008:
A series of 13 blasts occurred in and around Guwahati in the northeastern state of Assam, killing at least 70 and wounding more than 300 others.
Sept. 13, 2008:
Eighteen people were killed and over 90 others injured in various parts of the Indian capital New Delhi.
July 26, 2008:
At least 45 people were killed and more than 100 wounded after a series of 18 blasts in India's western city of Ahmedabad.
May 13, 2008:
At least 60 people were killed and 150 others injured by eight blasts in Jaipur, capital city of the Indian state of Rajasthan.
Aug. 25, 2007:
Three explosions in the southern city of Hyderabad killed at least 42 people and injured some 50 others.
Feb. 19, 2007:
At least 66 passengers, including Pakistani nationals, were killed and over 20 others injured in a terror attack on the Samjhauta Express - "friendship train" between India and Pakistan in Panipat of Haryana state of India.
Sept. 8, 2006:
At least 31 people have been confirmed dead after four bomb blasts rocked Malegaon town of Maharashtra, and over 300 people were injured.
July 11, 2006:
Seven powerful bombs ripped through crowded commuter trains in Mumbai, killing at least 190 people and injuring 844 others.
March 7, 2006:
At least 28 people were killed and about 100 others injured when three serial explosions ripped through the crowded Hindu holy city of Varanasi in north India's Uttar Pradesh.
Feb. 28, 2006:
Militants detonated a powerful landmine, killing at least 55 tribal villagers aboard two trucks and injuring about 20 others in the central Indian state of Chhattisgarh.