Worried UK parents are asking to have tracking microchips implanted into their children following the murders of two 10-year-old girls, says scientist Kevin Warwick, who has implanted a chip in his arm that is connected to a computer in an ongoing experiment.

The operation would involve implanting a small transmitter about one inch long into the child’s arm or stomach, Warwick said. Tracking options include using a mobile phone network and transmitting a signal linked to a global positioning system.

Watches that perform a similar function are already commercially available in the United States, but they can be too easily removed and discarded, Warwick said.