The children, aged 10 and 11, ignored the life guards' warnings and were caught out by a strong current. The teenagers dangerously approached rocks from a breakwater. Seven life guards had to be deployed to prevent the youngsters from downing.
The parents got a good telling off. One couple was sitting at the beach club, while another couple had gone shopping.
"Parents should keep a good eye on their children when they go swimming, especially on busy days and when the sea is dangerous" says Bjorn Prasse of Blankenberge city cabinet.