Police say they are seriously concerned after several children were spotted swimming in the River Wear just a short distance from where two teenagers drowned.
Chloe Fowler and Tonibeth Purvis died almost two weeks ago.
Today, police issued another warning, urging people to stay away from open waters.
It comes as new figures reveal a surge in calls to emergency services for people in trouble in the water.
More top news
39-year-old Julie Parkin, from Kirkwall Close in Castletown, was found with fatal injuries in the early hours of Tuesday morning.
Alan Shearer is set to tee it up in the Hero Pro-Am at the British Masters, taking place in Newcastle.
TV comic Sarah Millican has confirmed three Teesside dates for next year.