Tennis player Jamie Murray - the brother of British number one Andy Murray - was caught up in the queues at passport control on Thursday night.
He tweeted these pictures, estimating that there must be a couple of thousand people waiting in line.
He added the hashtag #thirdrunwayanyone?
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He is believed to be one of the oldest victims in a worrying spate of recent knife crimes.
The new leader of the council at the centre of the Grenfell Tower fire has told ITV News she will not resign 'yet' after a furious backlash.
200 UK officers already working on the case are sifting through 15 tonnes of debris on each of the building's 24 floors.