A TEENAGER threw fire bombs onto the M3, bringing the motorway to a standstill for more than 11 hours and costing the region's economy £40 million.

Nicholas Elger, 17, who can now be identified following previous restrictions, pleaded guilty to two charges of arson recklessly endangering life in December, with a not guilty plea to two charges of causing danger to road users accepted by the prosecution.

The incident on the M3 closed the stretch between junctions 9 and 11 for 11 hours on September 23, causing traffic chaos in the region.

Prosecuting, Rob Welling told Winchester Crown Court that a voice had told Elger to kill and he subsequently threw “fire bombs” onto the southbound carriageway on two separate incidents.

Both devices were thrown to coincide with vehicles passing under the bridge.

Bomb disposal experts were called to investigate the “potentially hazardous material” that was thrown onto the carriageway from a motorway bridge. It was later discovered to be flammable but not explosive.

Officers also confirmed that a similar incident happened on the same motorway bridge the previous Saturday.

The teenager, who was detained at a mental health hospital prior to sentencing at Winchester Crown Court today, had previously pleaded guilty to eight counts of burglary against Winchester College – during which computer equipment estimates to be worth more than £37,000 was stolen – and two charges of blackmail with menaces against the school, each time demanding payment of £20,000 in the online currency bitcoin.

The court also heard Elger, who was a boarding student at the prestigious Winchester College, had a drawer full of matches as well a knife with the name James carved into it – the names of an alter ego he had created.

Mr Welling added that Elger’s house master James Fox had been concerned by his behaviour.

Mitigating, Robert Morris said the he had been make improvement while undergoing treatment and that the voices had diminished.

Judge Keith Cutler imposed a hospital order detaining Elger at a mental health facility while a psychiatric evaluation is completed. The case will be reviewed again in May.