Candie Gardens was closed while police searched the area following arrests for an alleged drug deal.
A 24-year-old woman has been arrested on suspicion of possessing a controlled drug. A 17-year-old boy has also been arrested for obstructing police and resisting arrest.
Police say the drugs are believed to be prescription medication.
Police have been using the park to train and exercise the force dogs while the Renoir exhibition is held at Candie Museum.
The art installation is still accessible while the gardens are closed.
UPDATE
Police are now appealing for dashcam footage of a 'young man' who got into a vehicle which attempted to leave the scene while being chased by police.
Anyone with information should call police on 01481 222222 or Crimestoppers anonymously on 0800 555 111.
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