NEW DELHI, India (CNN) -- A series of blasts ripped nearly simultaneously Thursday through crowded areas of a remote state in India, killing 62 people and wounding 300, an official in Assam state told CNN.

A man tries to extinguish a fire after one of the blasts in northeastern India on Thursday. more photos »

Assam Home Commissioner Rajiv Kumar Bora said other small blasts occurred in the northeastern state in addition to the nine bombs; authorities believe those may be from kitchen gas cylinders, he said.

Following the explosions, black smoke poured into the air. On the ground, charred and burned vehicles, their windows punched out and their metal frames mangled, remained on the streets. Police officers combed areas afterward for unexploded bombs, authorities said. Watch more about the blasts »

No one claimed responsibility for the attacks, some of which police said occurred in the state capital, Guwahati, in Kamrup district. Other bombs exploded in the Kokrajhar, Barpeta and Bongaigaon districts, police said.

Bora named the United Liberation Front of Asom -- a separatist group that has waged a 20-year rebellion demanding more autonomy from the central government -- as a suspect in the attacks. ULFA denies wrongdoing, he said. Images from the devastating blasts »

"Although ULFA has denied involvement, it is one of the suspects," he said.

Earlier, Assam's superintendent of police said both local insurgents and separatist organizations were being investigated.

India's president, Pratibha Devisingh Patil, condemned the attack in a written statement. "There is no place for violence in our society," the statement said.

The prime minister, Manmohan Singh, also condemned the blasts. "Such barbaric acts targeting innocent men, women and children only highlight the desperation and cowardice of those responsible," he said in a written statement.

"I am confident that the people of India will rise unitedly against these attempts to disturb peace and harmony and to destroy our social fabric. We will take all possible steps to maintain peace and bring the perpetrators of such acts to justice."

Three other blasts in Assam this year were blamed on the ULFA. iReport.com: Are you there? Share your photos, videos

The group is also blamed for the deaths of 42 migrant workers in a series of small arms attacks in January 2007 and for bombing an Indian paramilitary forces bus in 2004.

There also have been clashes between local tribal people, known as the Bodo, and immigrants from Bangladesh, with which Assam shares a porous border. Fighting between the two groups killed at least 47 this month.

-- CNN's Harmeet Singh and Bharati Naik contributed to this report.

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