Toronto, Aug 10 (IANS): With rioters in Britain using BlackBerry to direct fellow looters to spread mayhem in cities across the country, Blackberry maker Research In Motion (RIM) has promised to cooperate with British authorities.

The riots erupted last week after police shot dead 29-year-old Mark Duggan who in last message to his girlfriend from his BlackBerry said: "The Feds are following me.''

Since then, rioters have made extensive use of BlackBerry to send encrypted messages to mobs to riot, the Globe and Mail said in a report from London.

"If you're down for making money, we're about to go hard in east London," read BlackBerry message from one looter, the report said.

Other rioters used the encrypted smart phone to direct looters to stores selling expensive stereo equipment, designer clothes, alcohol and bicycle, the report added.

It said masked or hooded youths could be seen typing messages on their cell phones as rioting engulfed shops, vehicles and buildings in British cities.

BlackBerry's messaging system (BBM), which comes free, is used by over 45 million people worldwide to instantly convey text messages and pictures. Since BBM messages are encrypted, police cannot trace them. .

Blackberry has rejected demand from British lawmaker David Lammy, who represents the riot-hit Tottenham area, for suspending its messaging service, saying that shutting down BBM will hit more than 45 million people who use it globally.

But the BlackBerry company, based at Waterloo near Toronto, has said that it is complying with British legislation on interception of messages and co-operating with Scotland Yard. Hackers reportedly compromised BlackBerry's blog site in retaliation for its promise to co-operate with British police, the report said.