A large patch of burnt tar was recently dumped on the path and garigue close to Ix-Xagħra l-Ħamra at the Majjistral Park, near Għajn Tuffieħa.
The park’s management said fresh dumping was also found in the barracks area where, despite continuous clean-ups, picnickers kept leaving their rubbish behind.
The barracks area is being surveyed for eventual restoration after hundreds of volunteers helped to clean up the site.