Cambodia said on Friday it had closed more than 700 online scam centres in a crackdown over the past year, detaining nearly 30,000 suspects including a clutch of senior government officials.The Southeast Asian country has emerged as a hub for crime syndicates running fake romantic relationship and cryptocurrency investment schemes in which scammers, some willing, others trafficked, defraud internet users around the world.But under pressure from several countries including the United States and China, Cambodian authorities say they are cracking down on the industry.A government statement said on Friday authorities had cleared more than 700 compounds and deported 58,266 foreign nationals over the past year.It said nearly 30,000 suspects had been arrested, including 15 high-ranking officials and law enforcement officers.More than 3,400 suspects from 29 countries, including citizens from China, Vietnam, Australia, France, Japan, South Korea, Singapore and Thailand, were in custody awaiting trial.”Although large-scale sites have been completely cleared, criminal groups have altered their tactics to decentralised, small-scale activities, hiding in guesthouses, condominiums, rental houses, vehicles and coffee shops,” the government said.Cambodia extradited alleged scam boss Chen Zhi, the Chinese-born chairman of multi-billion-dollar Cambodian conglomerate Prince Holding Group, to China in January after he was sanctioned by the US and UK governments.In April, Cambodia also extradited to China Li Xiong, the Chinese-born former chairman of Huione Group, whom Beijing accuses of playing a key role in a major transnational gambling and fraud syndicate.The UN Office on Drugs and Crime (UNODC) said last year that hundreds of industrial-scale scam centres across Asia generate just under $40 billion (€35 billion) in annual profits.