GUWAHATI (India) - INDIA'S security forces are planning to mix one of the world's hottest chilli powders in hand grenades to control riots and during insurgency operations in the remote north-east, a defence official said on Thursday.

India's defence scientists say they will replace explosives in small hand grenades with a certain variety of red chilli to immobilise a person without killing him.

'We are working on a project on how to use the hottest chilli in different applications in defence forces,' said Dr RB Srivastava, a senior scientist at the state-run Defence Research and Development Organisation (DRDO).

Scientists said the chilli found in the country's north-east generates so much heat it was enough to startle a person for a while when used as a weapon.

The bhut jolokia chilli is said to generate 1,000,000 heat units on the Scoville scale - a measure of hotness - at least a thousand times more than a common kitchen chilli.

The Scoville scale was named after American scientist Wilbur Scoville, the first to measure the heat component in chillies.

The chilli will also be used as a food supplement for soldiers deployed in cold weather conditions to raise their body temperatures, Dr Srivastava said.

Scientists are also hoping to use a coat of the chilli powder in fences around army barracks as its pungent smell keeps wild animals away.

Pepper spray, which contains a chemical derived from peppers, is another commonly used riot control agent in many parts of the world. -- REUTERS