A bike-riding 15-year-old was snapped smashing the window of the unmarked van – the FOURTH time he has been caught out in similar police stings.

Amazing footage also shows how a blundering car thief hurled a brick at the van on Preston's Trees estate – only for it to bounce back and almost knock him out.

Jack Murphy, 20, of Cedar Road, Ribbleton, then managed to smash the window and steal a satnav.

But unfortunately for him, the satnav was fitted with a tracker – leading police directly to a bin where he had stashed it.

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He was jailed for 120 days after pleading guilty at Preston Magistrates Court.

The 15-year-old denied his offence – but was locked up for six months after being convicted by Preston magistrates of theft from a motor vehicle.

Both were filmed by a rat-trap van rigged up to catch the criminals in the act.

Detectives today claimed the honeytrap sting had helped them solve hundreds of offences.

Det Sgt Keith Lee, of Preston CID, said: "Sometimes just one offender can be responsible for a raft of crimes and if they are caught by the rat trap they often plead guilty to several other car crimes.

"However it can be hit and miss – we can't just use it on the off chance someone walking past could steal something. It has to be targeted to a specific offender or hotspot area."

Yobs on the Trees Estate have been snared eight times by the technique – with more than 40 offenders across the city collared in the last two years.

Det Sgt Lee said: "We put different items on display in our rat trap vehicles to catch the attention of thieves.

"Sometimes they may have cameras inside but often we can film the thief in action from an external hidden camera.

"On some occasions the car is rigged so that when they break in they are sprayed with Smartwater which clings to their hair, skin and clothes.

"When they are brought into custody they are walked through a UV tunnel that shows the substance up on them. The evidence is unquestionable."

In April Preston had a surge in thefts from cars.

Figures show there were 193 thefts in that month. In April 2007 there were 138 – including the pictured incident involving Murphy.

But a crackdown using rat traps helped officers catch three offenders. Since then car thefts have fallen month on month compared to last year.

In July so far there have been 43 thefts from cars compared to 64 the same time last year.

Detectives say that of 1,429 thefts from vehicles in Preston in 2007/8, almost a fifth were sat navs.

Anyone with information on car crime should call police on 01772 203203 or Crimestoppers on 0800 555111.

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