The NHS is potentially vulnerable to fraud due to loopholes in the issuing of European Health Insurance cards, the Department of Health has admitted.
An investigation by the Daily Mail found people who had never worked in Britain were able to obtain a free EHIC card in the UK, the paper says.
Health services abroad were then able to claim back the costs of their treatment from the UK authorities.
The government said it would look urgently at tightening the system.
The EHIC is designed to cover the cost of state-provided healthcare for British travellers in certain European countries.
It covers emergency treatment and certain pre-existing medical conditions, and routine maternity care, providing the reason for a patient's visit is not specifically to give birth.
To obtain a card online, an applicant must provide a personal NHS number, which is allocated upon registration at a GP practice.
http://www.bbc.co.uk/news/health-33843758