More than 100 tonnes of gold has been returned from London to Poland in a top-secret repatriation mission.The haul worth around $5bn (£3.85bn) was transported from a secret location near the capital to an unknown airport in London, accompanied by a police escort and a helicopter, and loaded onto a freighter plane and flown off to Poland.Amid the outbreak of the Second World War, the entire Polish gold reserves were secretly transported across three continents to be stored in London, New York and Ottawa.Now, Poland has seen the gold that was kept in the UK returned to them and placed in a high-security location.When it arrived in Poland on 22 November, the gold was loaded into three armoured vehicles and accompanied with a full motorcade to undisclosed vaults.Image:The gold was moved in the middle of the night.

Pic: G4SImage:Poland has stored the gold at a secret location.

Pic: G4SIt took eight trips to transport the gold back to Narodowy Bank Polski, the country's central bank, where it will now be kept.Each bullion was a standard issue London Good Delivery bar, which weighed 12.5kg each and were stamped with a serial number and marker which showed the place they were produced.G4S Cash Solutions UK handled the operation.

The firm's director John Lennox said: "The movements of the gold were meticulously planned in co-ordination with everyone, including the police, the Bank of England, the Narodowy Bank Polski and G4S."Given the sensitivity this operation, we needed to be prepared for anything.

Plans can change at short notice.

Having a strong team, flexible and professional drivers, and making sure everyone was regularly updated meant the operation was a complete success."Image:More than 100 tonnes of gold were moved by G4S.

Pic: G4SG4S' managing director, Julian Haskard, called the repatriation operation a "historic day in the gold industry".Poland's banking chief confirmed that the transfer of the gold had been completed, and added that a commemorative coin will be minted to celebrate.:: Listen now on Apple Podcasts, Spotify, Google Podcasts, SpreakerAs well as the original bars, Poland announced last year it would be buying a further 100 tonnes of gold, to give reserves a boost.According to Bloomberg, the country had $121.9bn (£93.7bn) in its official reserves, including gold, as of the end of October.