AT FIRST it did not seem an untypical riverside scene: two teenagers relaxing with drinks alongside Yarmouth's Haven Bridge.But then, oblivious to drivers passing over the bridge in the early afternoon rush hour, one of them suddenly stepped out, using metal work on the bridge like monkey bars to swing out over the fast-flowing River Yare.

AT FIRST it did not seem an untypical riverside scene: two teenagers relaxing with drinks alongside Yarmouth's Haven Bridge.

But then, oblivious to drivers passing over the bridge in the early afternoon rush hour, one of them suddenly stepped out, using metal work on the bridge like monkey bars to swing out over the fast-flowing River Yare.

The “moment of complete madness” took away the breath of retired Royal Naval Reserve Commander Mike Souter, who recorded the whole escapade on camera.

Freelance journalist Mr Souter had been out on patrol with Broads Authority navigation rangers when the drama unfolded at about 4.30pm on Monday.

He said: “The Broads Authority launch River Able moved under the bridge in case the kid fell off but the pair appeared to be goading the rangers by their actions.

“The escapade was complete madness. There was a fast-flowing ebb tide and if he had fallen, he would have been propelled out to sea at a speed of seven or eight knots.

“Anyone at all familiar with Breydon Water knows this is the most dangerous stretch of water on the Broads.”

Navigation ranger Joan Derhe said they alerted the coastguard and police straightaway but the youths ran off before anyone arrived.

She said the bridge was outside the Broads Authority's navigation area but they had gone to help realising the potential danger.

“Apart from the tide and currents there was also the danger posed by commercial river traffic,” she said.

“It was the utmost stupidity. There only needed to have been a bit of oil on the metalwork and he could have lost his grip. He might not have even come up again.”

She said the incident served as a reminder to families to be vigilant about water safety with the approach of the school summer holidays.

She said: “Alcohol and water don't mix, and for those out on boats it is important to always wear lifejackets on board.”

A coastguard spokesman said: “This action was extremely foolhardy. With eddies, and the obstructions under there, you

would not stand a chance if you fell in.”