Coastguards say jet skiers have been riding deliberately towards swimmers and even children playing in the sea, putting them in danger.
The warm weather has seen an increase in the machines being used along the coast but some are flouting by-laws and are riding too close to the beach.
Charlotte Wilkins reports and speaks to Solent coastguard Carey MacKinnon, jet skier Simone Smith and watersports enthusiast Paul Richards.
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Russia has announced that it will expel 23 UK diplomats in a deepening rift over the poisoning of a Russian ex-spy and his daughter.
Scores of flights were cancelled and drivers were warned to take care as the "mini beast from the east" swept in.
Sergei Skripal, the ex-Russian spy who was the target of the attack, and his daughter Yulia, remain in a critical but stable condition.