Thousands of passengers have had their travel plans thrown into chaos after a busy city airport in London had to close so repairs could be made to the runway.

London City Airport (LCY) should have opened at about 6am – but an early-morning inspection of the runway found surface problems and no flights were possible in or out.

As passengers filled the airport terminal in Docklands, repairs were being carried out, with the hope that services could start again around midday.

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An LCY spokesman denied suggestions that there was a hole in the runway and apologised to passengers for the inconvenience.

Keith Gill tweeted: “London City. It’s a complete nightmare. No communication/updates.”

Andy Richardson wrote: “Chaos at London City this morning causing us problems flying in from Scotland.”

Amid a grim situation for passengers, some saw the funny side of things.

Brid Cannon tweeted: “So, nocturnal alien landings leave their mark on runway at London City. Repair crews cleaning up after the ‘visit’.”

An LCY spokesman said the runway was inspected each night before close at about 10.30pm, and inspected again before it reopened at 6am.

“Today’s early inspection found there was a need for maintenance. There is not a hole in the runway but there is a surface problem. There are inconsistencies on the surface of the runway.”

Passengers were being advised to check with their airline before leaving for LCY.