It had been swept away in strong river currents during floods in north-east India before being found in neighbouring Bangladesh.

Locals gave it the name Bangabahadur, meaning Hero of Bengal.

It may have travelled 1,700 km (1,060 miles) but was weakened by its journey and attempts to tranquilise it, and is thought to have had a heart attack.

A post-mortem examination has been ordered.

A local newspaper quoted vet Mustafizur Rahman as saying the elephant had a heart attack - with stress, dehydration and electrolyte imbalance being factors.

After it collapsed, rescuers administered 12 litres of saline but could not revive the animal.

Thought to weigh about four tonnes, the elephant had become progressively weaker after spending weeks in flood waters.

Without proper food the animal gradually lost its strength.

'Our luck is bad'
Wildlife officials tried to transport it to a safari park - tranquilising it repeatedly - but failed as the animal could not be tamed.

The Bangladeshi government's chief wildlife conservator Ashit Ranjan Paul told AFP news agency: "We have given our highest effort to save the animal. At least 10 forest rangers, vets and policemen have constantly followed it for the last 48 days.

"But our luck is bad."

Its rescue was dramatic. Once the elephant was tranquillised, it fell into a pond where villagers saved it from drowning and then helped pull it out.

One man was injured after the elephant kicked him.

Floods force thousand of animals to move to higher ground every year in the border areas between the two countries.

The shrinking natural habitat of wildlife animals has made it increasingly difficult for them to move to safer areas during monsoon floods.

(BBC News)