Thirteen people have been arrested as police smashed a people-smuggling ring during raids across England.Eleven addresses were raided in London and Kidderminster, Worcestershire, during Operation Greensea targeting the gang which is suspected of bringing potentially hundreds of illegal migrants into the UK.The majority of suspects are believed to belong to a gang of Turkish people-smugglers who specialise in trafficking Chinese nationals.Senior officers said suspected traffickers from every rung of the criminal ladder were among those arrested, including two "Mr Bigs".Police said some of the properties at the centre of the raids were home to up to 30 illegal migrant workers. It follows similar raids by police in Belgium and France over the past few weeks.The operation followed 12 months of surveillance and information gathering, led by Scotland Yard's serious and organised crime unit.Senior officers said the Turkish gang is responsible for the final leg of a journey that could take the Chinese migrants up to 18 months to complete.Each person would pay up to £21,000 to be brought across Asia into western Europe and eventually Britain, netting the traffickers huge sums.Most of migrants come from Fujian province in south east China where there is a culture of sending people overseas to earn money for their family.The journey takes many months because the migrants are often forced to wait at safe houses en route as the next stage of their journey is organised.Detective Superintendent Steve Richardson, of Scotland Yard, said: "The scope to make substantial sums of money is definitely there in this criminal network as there is with drugs."Somebody can make a very reasonable living if they have their routes set up and their network in place. We have today dismantled two organised criminal networks involved in what is suspected to be large-scale human smuggling into the UK."We are committed to taking out these networks and this operation is the latest in our collaboration with a growing number of law enforcement agencies in Europe and the UK to work robustly to achieve this mission."© Independent Television News Limited 2008. All rights reserved.