- Vandals used a hammer and screwdriver to vandalise the Stonehenge ancient monument, the first such incident for decades, officials said Thursday.

The night-time attack by two men last week involved the central megalith in the 5,000-year-old ring of standing stones, with English Heritage saying the vandals could have been looking for a souvenir.
A chip of stone about the size of a large coin was removed, while a 2.5-inch long scratch was left on the Heel Stone, at the centre of the UNESCO World Heritage Site, near Salisbury.

"Thanks to the vigilance and quick action of the security team at Stonehenge, very minimal damage was caused," said a spokeswoman for English Heritage.

"A tiny chip was taken from the north side of the Heel Stone with a screwdriver and hammer, but as soon as the two men were spotted by security guards they escaped over the fence and drove off.

"This is now a matter for the police," she added.

A spokeswoman for Wiltshire Police said: "Two male offenders were seen disturbing the monument with a hammer and screwdriver... It is believed they could be two men seen acting suspiciously on a previous occasion."

Stonehenge is one of the world's best preserved prehistic monuments. In around 2,600 BC, 80 giant standing stones were arranged on Salisbury Plain, where there was already a 400-year-old stone circle.

Around two centuries later, even bigger stones were brought to the plain.

Today, only 40 percent of the originals remain. But around 850,000 visitors per year come to marvel at the 17 stones which are still intact.

The biggest stones came from a quarry some 18 miles away, while some of the others come from a range of hills in south-west Wales -- a 150 mile journey.