Tens of thousands of migrants are working with vulnerable elderly people in care homes without undergoing full criminal record checks, The Times has learnt.
Senior police officers have alerted Jacqui Smith, the Home Secretary, to the scale of the problem in a report detailing the impact on the UK of migration from Eastern Europe.
The introduction of a watchdog next year to vet care workers will not address the problem, they add.
It is estimated that about 400,000 elderly people are being looked after in care homes. This figure is expected to reach 750,000 by 2031 as more and more people live longer. Many of the homes would be unable to operate without employing foreign workers, as British workers are unwilling to take the jobs.