Drunken elephants have trampled at least six people to death in the northeast Indian state of Assam, local officials say.

The herd of wild elephants stumbled across the supplies of homemade rice beer after they destroyed granaries in search of food.

The incident happened near Tinsukia, 550 kilometres (344 miles) from the Assam capital, Guwahati.

"They smashed huts and plundered granaries and broke open casks to drink rice beer. The herd then went berserk killing six people," a forestry official told AFP news agency.

Police said four of those killed were children.

According to experts, elephants often emerge from Assam's forests in search of food.

But much to the annoyance of the local residents, they destroy rice fields and granaries.

Environmental questions

Growing elephant numbers and the devastation of the animal's natural habitat are partly to blame for the problem.

Officials in Assam say at least 150 people have been killed by elephants in the last two years.

The deaths have led villagers to kill up to 200 elephants.

"It has been noticed that elephants have developed a taste for rice beer and local liquor and they always look for it when they invade villages," an elephant expert in Guwahati told Reuters news agency.

The region is home to more than half of India's elephant population, estimated at 10,000.

The Assam Government's protection of elephants over the last 20 years, including a ban on their hunting, has led numbers to increase to about 5,500.