Police are appealing for information after a lifebuoy was stolen from near the River Wensum in Norwich.
The safety device was taken from St Georges Street, near Norwich Playhouse, at around 12.30am on Wednesday, May 17.
A police spokesman said the suspect then ran off towards Colegate and Oak Street.
Caroline Richardson, director of Norwich Playhouse, which is by the river, stressed the importance of lifebuoys.
She said: 'I don't think we have ever had anyone in need of one here, but they are important because they save lives.'
It is understood that the lifebuoy has been returned.
But police are still looking to speak with witnesses or anyone who has information regarding the incident.
They are asked to contact PC Mick Pearce at Bethel Street Police Station on 101.
Alternatively, people can contact the charity Crimestoppers anonymously on 0800 555 111.
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