As part of Operation Sceptre and Operation Guardian, officers used metal detectors and their hands to check undergrowth for knives hidden by people intent on causing violence.
Dudley Town Police tweeted: "Officers alongside a metal detector operator have collaborated and attended multiple park areas for Operation Guardian, knives and heavy tools have been discovered and seized."
Heath Town and East Park Police tweeted: "Knife sweep around East Park today. Nothing found on this occasion. We got deep into the growth to check for anything that could be discarded."
Penn and Tettenhall Police PCSOs checked canal paths for weapons.
Penn Police tweeted: "PCSO Wright and PCSO Brookes have been down the canal path in Pendeford conducting a knife sweep and engaging with the community, Operation Sceptre."