Oct. 30 (Bloomberg) -- More than 60 people were killed and about 300 injured in 12 bombings across the eastern Indian state of Assam, where indigenous groups have clashed this month with immigrants from neighboring Bangladesh.

Devices containing high-intensity explosives were detonated between 11 a.m. and noon today, mostly in crowded places, state Health Minister Himanta Biswa Sarma said in a phone interview. No group has claimed responsibility, and police are investigating if the attacks were carried out jointly by a rebel organization and Islamist militants, he said.

President Pratibha Devisingh Patil and Prime Minister Manmohan Singh condemned the attacks that follow ethnic clashes in the tea- and oil-rich state and a wave of 40 bombings that have killed 175 people across India in the past five months.

``Such barbaric acts targeting innocent men, women and children only highlight the desperation and cowardice of those responsible,'' Singh said in an e-mailed statement. ``We will take all possible steps to maintain peace and bring the perpetrators of such acts to justice.''

Long-standing disputes over land between members of the Bodo tribe and Muslim settlers from Bangladesh turned violent this month when 57 people were killed in clashes, including 25 when police opened fire on protestors. The dispute began Oct. 3 in the Udalguri district and spread to other areas.

Assam, which also shares a border with Bhutan, is home to several rebel groups, including the United Liberation Front of Asom, or ULFA. At least 314 security personnel and civilians were killed last year in violence in the state.

The attacks were in the city of Guwahati and Barpeta, Bongaigaon and Kokrajhar districts, Sarma said.

No Evidence

``We are suspecting there can be a combination of ULFA and some Jehadi elements behind the blasts,'' Sarma said, adding that authorities had no evidence to support this. ``This is a very premature observation.''

The outlawed ULFA denied any role in the blasts, the Press Trust of India reported, citing an e-mail statement signed by Aanjan Borthakur of the group's central publicity unit.

The curfew imposed in some parts of Guwahati following protests by residents has been lifted, Sarma said.

Cities and towns across India have been targeted this year, with devices strapped to bicycles, hidden under auditorium seats and left near market stalls. Blasts on Oct. 21 in Imphal, capital of the northeastern state of Manipur, left at least 17 people dead.

Today's explosions came six weeks after five blasts in the capital New Delhi that killed 26 people, the worst terrorist attack since 56 people died in explosions in the western city of Ahmedabad on July 26.

Recent terrorist attacks in India have been carried out by a group called the Indian Mujahideen, which claimed responsibility for explosions in Jaipur, Ahmedabad and New Delhi. The Jaipur blasts, which took place on May 13, killed at least 68 people.

To contact the reporter on this story: Bibhudatta Pradhan in New Delhi at bpradhan@bloomberg.net.

Last Updated: October 30, 2008 11:11 EDT