Drug tests on prisoners in Dutch jails and secure psychiatric units show the use of cannabis is widespread, news agency ANP said on Thursday.

Thousands of urine samples have proved positive for drugs, with the rate as high as 50% in some jails, ANP said. The figures come from justice ministry figures which have not yet been made public.

In total, the tests resulted in 16,600 positives for cannabis, compared with 14,500 in 2014. There were 1,600 positive tests for cocaine and 730 for opiates, such as heroin. More than 1,000 positive tests for cannabis per jail were not unusual, ANP said.

The true size of the drugs problem in Dutch jails may be far higher because not all prisoners are tested. Yet while the tests are random but people considered likely to use drugs or who are repeat offenders are more likely to be singled out, ANP said.

Improvements

The justice ministry told ANP in a statement that officials work continually on improving drug checks. ‘Addiction clinics are also involved to increase awareness of the problem among staff,’ the ministry said.

Prisoners, particularly addicts, are extremely inventive in how they obtain their drugs and the prison inspectorate said in a recent report that the shortage of staff makes it difficult to keep drugs out of jails.

Union spokesman Frans Carbo told ANP: ‘This is yet another sign that policy needs to be radically overhauled so that staff work in a safe environment. The cuts made in recent years have severely threatened this.’

Last September, local broadcaster Omroep Brabant reported that a woman had been caught attempting to smuggle soft drugs into the prison at Vught using a three-year-old child.