Heavy rain brought part of the ceiling down at a McDonald's restaurant near Norwich.
The restaurant at Longwater Retail Park near Norwich was closed for an hour and a half after the incident, which happened in Tuesday's deluge.
Seventeen-year-old Joel Cooper, of Crown Road, Dereham, had just left the restaurant with friends when the incident happened.
Mr Cooper, who attends college in King's Lynn, said: 'It was a strange thing to experience.
'We saw the ceiling had collapsed right where we were sitting and if we had have left 30 seconds later we would have been harmed.
'Electric cables fell down and water.
'The scary part is that it could have happened at any time of day.'
A spokesman from McDonald's confirmed that a leak had started on Tuesday afternoon.
He added: 'I can confirm that due to heavy rain on Tuesday, a small corner section of the dining area ceiling and plasterwork was damaged.
'We are currently assessing the extent of the work required, but the restaurant is trading 24/7 as normal and we do not envisage closing whilst repair works take place.'
• Have you had something unusual happen to you? Contact reporter Donna-Louise Bishop on 01603 693892, email donna-louise.bishop@archant.co.uk or follow on Twitter @donnaloubishop.
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