Police are hunting a man who has attacked at least four women in Amsterdam’s Vondelpark by smearing them with a putrid substance.

Since August police have recorded eight incidents which they believe involved the same man, most of which took place in the early morning, AT5 reported.

The most recent victim was a 14-year-old girl who was kicked from behind in the knees before a foul-smelling substance was rubbed in her face. Tests are being carried out to find out what it was.

The incident happened last Friday at about 8am on the bridge near the rose garden. Police received a report later in the day of an attempted attack with a similar substance.

On the morning of October 13 two women were attacked in separate incidents as they cycled through the park between 6am and 6.30am. The previous weekend a woman was pushed off her bike in nearby Leidseplein.

Police spokesman Frans Zuiderhoek said: ‘In the first instance we have put extra security in place to see if we can catch this man in the act. Up till now we have not been successful and the attacks are becoming increasingly aggressive, so we are appealing to the public to help us.’