A police cold case team looking into 85 unsolved murders says it may have identified a possible serial killer responsible for murdering five women over the past 30 years.

Four of the women had their throats cut, they had all been subjected to similar sexual practices and all five were covered up in similar ways, a police spokeswoman said.

At least 127 prostitutes have been murdered in the Netherlands over the past 30 years, of which just 42 cases have been solved.

The police are also considering using new DNA techniques in the remaining cases in an effort to bring the killers to justice, news agency ANP reported. They also want changes in the law which limits DNA-based identification to eye colour. Hair and skin colour can also be determined from DNA, the news agency said.

The public prosecution department is also considering large-scale DNA testing in an effort to solve a further 20 to 25 unsolved deaths. A mass call for DNA samples led to the murder of schoolgirl Marianne Vaatstra being solved last year.