Police are asking Central Hawke's Bay residents to be vigilant when using parks around the district, after incidents of "malicious vandalism".
CHB Police officer in charge, Sergeant Neil Baker, says bolts have been loosened on swings at Adeane and Russell parks in Waipukurau, and at parks in Waipawa and Takapau.
"This puts the public in danger - especially young children" says Sergeant Baker.
The council has increased the surveillance of the playgrounds and is asking for the public's help to spot and report any damage to playground equipment, on the council's 24-hour phone line, 06 857 8060.
Council and Police also ask people any suspicious activity using the Police non-emergency phone number, 105.