MADRID (AP) — Spain's Civil Guard says it has arrested six people for possibly swindling 1.8 million euros ($2 million) from elderly people held at an alleged "house of horrors."

In a tweet, the police force said it found foreign elders locked up, drugged and often fed through tubes at the private nursing home near the southern city of Cadiz. An elderly German man and a Dutch woman were found to be in a "terrible state."

According to the local Diario de Cadiz newspaper, a Cuban woman and a German man were among those arrested over allegations that they duped the elders to designate them as heirs.

The report said Interpol was first alerted by a friend of one of the residents.