LONDON: British troops brought in at short notice to help with security at the Olympic Games were summoned to the rescue for a second time on Sunday - this time in the less arduous role of filling empty seats.

The Games organising committee, LOCOG, turned to the army again after television footage of rows of empty seats at many venues caused outrage among Britons who had tried and failed to buy tickets under a complex allocation system.

“LOCOG has kindly offered service men and women working on venue security to make use of unutilised seating when they are off duty,” a Ministry of Defence spokesman said.

“These seats will be made available to venue security personnel to utilise on a voluntary basis when off duty.”

Earlier this month, the government was forced to deploy an extra 3,500 troops - some of them just back from stints in Afghanistan - after private contractor G4S failed to meet its commitment to supply 10,400 security guards.

The armed forces are now in charge of airport-style checks at several venues including the media centres, easing safety concerns in a city that was hit by bombing attacks in 2005, hours after being awarded the Olympics.

Troops from the elite Parachute Regiment have been searching buses at a roadblock going into the Olympic park.

One soldier with 18 years' service told Reuters he had learned only on Tuesday that he would be on Games duty, sharing makeshift accommodation in a room with 30 others in east London, and had had to cancel his holiday and break the news to his wife.

Others, enjoying the unexpected bonus of tickets to the women's gymnastics on Sunday, said they had been told they could not speak to the press.

The army enjoys strong public support in Britain, a reflection of widespread sympathy and respect for its losses in the wars in Afghanistan and Iraq. Troops are not normally deployed at home except to guarantee essential public services during emergencies.