Gloucestershire Police are warning people not to buy Olympic and Paralympic Games tickets from advertisements that just feature a mobile phone number or email address.
They say there's a risk of paying over the odds for tickets that may not exist and your personal details may be stolen and used in other crimes.
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It will be a breezy start, with clouds arriving around lunchtime. The afternoon will be sunny with showers.
Tuesday will start dry and bright with lighter winds, before cloud thickens bringing some outbreaks of rain through the afternoon.
The day's gusts will ease as the evening goes on. It will be mostly dry with cloud cover but occasional clear spells.