Two more British tourists have died in Amsterdam after taking white heroin which had been sold to them as cocaine, Dutch police said on Monday.

The men, aged 20 and 21, were found dead in their hotel room in the Amsterdam district of Zuid on Tuesday.

Tests carried out by the Dutch forensic institute show the make-up of the drug is the same as that involved in the death of another British tourist at the end of October. Three other British tourists became ill after taking the drug at the beginning of this month.

‘It would appear that tourists who come to Amsterdam are being seen as easy victims because they don’t know what is safe,’ a police spokesman told the AD.

Amsterdam’s health board has been warning tourists about the dangers of buying cocaine from street dealers since the end of last month, including the use of a large illuminated sign on the city’s Rembrandtplein.

Drug expert August de Loor told local broadcaster AT5 the drug is likely to have all come from the same dealer.