Customers in a Darlington jeweller's shop wrestled an armed raider to the ground last night.

But they released him when they were threatened with a gun at point-blank range, police have revealed.

The trouble started when three men, two armed with sawn-off shotguns and one carrying what was thought to be a pistol, burst into D&H Jewellers, in Houndgate, Darlington, County Durham, yesterday afternoon.

The raiders leapt over counters as they threatened staff, smashed display cases and grabbed expensive jewellery.

"At one point two of the people in the shop were caught up in a scuffle when one member of the gang was pinned to the ground," said a Durham Police spokesman.

"He was released when his would-be captors were threatened at point-blank range by one of the other gunmen."

The trio, carrying jewellery worth thousands of pounds, ran to a getaway car driven by a fourth man and sped off through the town centre despite the efforts of another trader to stop the vehicle.

Police said the neighbouring trader threw furniture at the silver-coloured car's windscreen as he tried to force it to halt.

Detectives have appealed for help in tracing the gang and were today studying CCTV footage in a bid to identify the robbers.