Scientists in India say they have identified the world's hottest chilli - nearly 50% more fiery that its nearest Mexican rival.

Experts at a defence research facility in the north-eastern state of Assam say the Naga Jolakia chilli measured a breathtaking 855 Scoville units as compared to the Mexican Red Savina Habanero's 577.

The Scoville unit is named after a German scientist, Wilbur Scoville, who was the first to measure the hotness of chillies.

The Mexican chilli had previously been considered the hottest in the world.

"Laboratory tests have confirmed that Naga Jolokia, a speciality from the north-east, is now the worlds hottest chilli," the laboratory's deputy director SC Das told the French news agency.

The Naga Jolokia grows to about five centimetres (two inches) long and to a thickness of one centimetre (0.4 inch).

Local favourite

It is said to be a firm favourite in the in the hilly countryside of Assam where it is grown, although a local chef was quoted as saying the only way to counter its fiery effect was to drink milk or dairy products rather than water.

It is not clear why the defence research scientists were researching the hotness of the chilli.

However, one researcher referred to the fact that chillies were used in ancient times to ward off enemies.

Chillies are a standard part of Indian cooking, used to vary the hotness of meals.

India is the world's top producer of chillies, exporting an estimated 35 tonnes a year.