The arrest on Saturday of a registered British sex offender, employed at a Phnom Penh school for the past year, has cast doubt on the screening of foreign nationals working with children in Cambodia.

With wanted sex offender Paul Prestidge’s extradition pending, the British Embassy yesterday issued an online reminder about the worldwide mechanism for intercepting UK child-sex offenders seeking employment overseas: the International Child Protection Certificate (ICPC), introduced in 2013.

However, children’s rights groups say such measures alone are insufficient to address the growing international problem of Western offenders travelling with impunity to countries where child-protection laws are weaker.

“We must acknowledge that the UK is responsible for exporting child abusers,” said Bharti Patel, CEO of the UK-based child protection NGO ECPAT, who notes a documented increase in British nationals convicted of sex offences against children abroad.

“The failure to manage UK sex offenders is shocking … We would like there to be more sharing of intelligence on high-risk individuals between agencies within and across borders.”

Prestidge, who previously served three years in prison on child-pornography-related charges, had been wanted in the UK since illegally travelling abroad in 2010, and was arrested last week after the British Embassy in Cambodia alerted immigration police to his presence in the country in September.

Prestidge, who was employed as a teacher at Hope International School, is the fourth foreign teacher to be arrested on child abuse charges in Cambodia this year. While endorsing the ICPC and other international intelligence-sharing initiatives by foreign embassies, local child protection authorities say the onus lies with individual employers to undertake due diligence.

“It is the responsibility of schools to step-up their efforts and demand screening of local and foreign staff,” said James McCabe, director of operations at the National Police’s Child Protection Unit. “There is no excuse for a modern, allegedly wealthy school failing in some of the most basic child protection measures.”

McCabe explained that the government is working towards risk-management strategies in conjunction with embassies, but that no national policy exists to enforce background checks in schools or other institutions working with children.

A spokesman for the Ministry of Education, Ros Salin, said state schools only hired foreign teachers under agreements with foreign governments or NGOs, and that it was up to private education providers to administer their own screening policies.

Organisations reliant on international funding are ordinarily bound by such policies on the part of their donors. However, Prestidge’s prolonged employment suggests that staff remain unpoliced in Cambodia’s numerous local education providers, provoking serious concern among child-rights NGOs.

In acknowledgment of the lure of developing countries to foreign sex offenders, the social welfare NGO Friends International founded Childsafe, a global child protection scheme that encourages businesses and organisations to institute socially responsible practices.

“Schools, universities and educational establishments should be safe places for children and young people,” said Friends’ James Sutherland. “Incidents such as this underline the crucial importance that in all such establishments, comprehensive child protection policies must be in place . . . including background checks.”

Hope International School declined to comment on whether the organisation conducted any such checks, but an employee from another reputable Phnom Penh school, who spoke on condition of anonymity, said yesterday that often local operators posing as Western-style schools shirked such responsibilities due to the cost.

However, staff from a number of other well-regarded international schools, including the Canadian International School and International School of Phnom Penh, confirmed that they conducted background checks on all employees.

The British Embassy did not respond to questions about any possible investigation into offences committed by Prestige in Cambodia or when they became aware of his presence in the country.