The deadly lure of deep water during sunny spells has once again proved fatal in Oxfordshire.

Italian teenager Angelo Gnerucci remains missing presumed drowned after jumping into the River Thames while out drinking with friends at Henley on Saturday.

It is the latest in a long list of tragedies and has prompted police to re-issue warnings to people to use extreme caution when temperatures rise and the chance to cool off in rivers and lakes seems irresistable. Thames Valley Police also took the opportunity to warn youngsters not to indulge in the dangerous 'sport' of jumping into the water from river bridges along the Thames another summer pastime which has also injured many people over the years. At Henley on Saturday, crowds strolled along the banks while others soaked up the sun from the riverside terrace of the popular Angel on the Bridge pub.

A 32-year-old man from one group decided to jump into the river, followed shortly by 19-year-old Mr Gnerucci who was drinking with another crowd nearby. Both appeared to get into difficulties in the fast-running water, but the older man managed to scramble clear. The teenager, who lived in Chalfont St Peter in Buckinghamshire, disappeared beneath the surface. His body had still not been recovered 48 hours later. The police warning was repeated by the mother of one of the last Oxfordshire river victims 14-year-old Ben Cross, of Wantage Road, Didcot, who drowned last summer after getting into difficulties while swimming near Wallingford Bridge.

Ben's mother, Sarah Cross, said yesterday: "My message to anyone is, simply, 'don't do it'.

They can't tell about the currents or anything. It's a very foolish thing to do."