A TEENAGER has been charged after 'flammable material' was allegedly thrown from motorway bridge causing 11 hours of travel chaos on the M3.

The 17-year-old boy, from Winchester, faces charges of arson with the intent to endanger life and causing danger to road users in connection with the incident on Saturday, September 23, as well as a similar incident on Saturday, September 16.

As previously reported, police closed the M3 near Winchester and bomb disposal experts were called to investigate the “potentially hazardous material” that was found in the carriageway between junctions 9 and 11, resulting in drivers being stranded on the motorway for more than 11 hours.

Hampshire Constabulary said that tests are still being carried out on the substance to find out exactly what it is after revealing it was thrown from a bridge in the early hours of Saturday morning. Officer confirmed that a similar incident happened on the same motorway bridge at about 4am the week before.

A government investigation is also being carried out into the handling of the situation after furious motorists complained that Highways England's warning regarding the closure weren't good enough.

One driver, Angela Nickerson, who regularly uses the M3, said: "The trouble is these signs and signals are totally insufficient in number and places to get the information out there. On the A34, which would link up with the M3, for example - where are these signs?

"Also, not everyone uses Twitter. I have never heard of the Traffic England website – and would I be looking at my internet as I was driving? Weekend radio traffic bulletins are few and far between despite there being as much traffic on roads as during the week."

However Highways England defended its response.

Customer service director Mel Clarke said: "We worked hard to give drivers accurate, up to date information about conditions on the M3 and to keep traffic moving as much as possible. We set up a diversion as soon as the closure had been implemented, and we set signs and signals across our network to warn drivers on approach about the closure.

"This was a serious incident and it was important that the police were able to conduct a thorough investigation. We believe we did everything we could do in the circumstances, but we routinely review our performance and will ensure we act on any opportunities to improve."

The boy has been remanded in police custody and is due appear at Basingstoke Magistrates’ Court on Monday.