The most important Viking treasure find in Britain for 150 years has been unearthed by a father and son while metal detecting in Yorkshire.

Metal detectorists David and Andrew Whelan, who uncovered the treasures, said the find was a "thing of dreams". The pair, from Leeds, said the hoard was worth about £750,000 as a conservative estimate.

The ancient objects come from as far afield as Afghanistan in the East and Ireland in the West, as well as what is now Russia, Scandinavia and continental Europe.

The hoard contains 617 silver coins and 65 other objects, including a gold arm-ring and a gilt silver vessel. Most of the smaller objects were extremely well preserved as they had been hidden inside the vessel, which was protected by a lead container.

It was probably buried for safety by a wealthy Viking leader during the unrest following the conquest of the Viking kingdom of Northumbria in AD927.