Violent images add sinister edge to phone messaging

Phone companies are reporting a growing number of "bluejackings" where anonymous messages or images are sent to strangers by mobile. The practice takes its name from Bluetooth technology, that allows individuals to send messages 10 metres to other phones without a number.

One bluejacking fan website, BluejackQ.com, carries an enthusiast's account of targeting a stranger from a nearby hiding point. After sending anonymous jibes about the victim's clothes and behaviour, the fan describes the satisfaction of seeing a "smile appear on her bewildered face".

'the fan describes the satisfaction of seeing a "smile appear on her bewildered face

Bluejacking is now turning more sinister, with reports of mobile phone users being sent violent or pornographic images. Marcia Gies, 21, a hotel worker from west London, was subjected to a "horrible" experience by an unknown bluejacker after returning from an evening with friends.

"I was half asleep on the night bus when my phone vibrated. It was a video message by an unnamed source," she said. "Without thinking, I opened it. It was violent, frightening pornography."

"I deleted the clip, thinking it must have been a strange mistake," she said. "Then I had another message, saying: 'Where's your boyfriend?'"

"The third message really scared me. It said: 'Which is your stop? Why don't you take your scarf off and give me a smile?' That's when I realised someone on the bus was watching me."

She added that lots of her friends had been bluejacked, including a school child who received a clip from a stranger that showed a hostage in Iraq being beheaded. "Now he can't get the image out of his head."

Owners of Bluetooth-enabled phones can block all anonymous messages, but ignorance of the technology and how to turn it off means many allow themselves to receive obscene texts or video clips.