London City Airport evacuation 'may have been caused by passenger accidentally discharging CS gas'

'The people behind the desk were coughing the most and quite aggressively. Within two minutes, they shouted for everyone to get out'

People outside London City Airport after dozens of passengers were treated for breathing difficulties (PA)

A suspected "chemical incident" that made dozens of people sick at London City Airport may have been caused by the accidental release of CS gas by a passenger before check-in .

Investigators looking into the cause of the incident – which saw people run from the facility as numerous passengers began coughing inside – found a canister believed to be CS gas or spray during a sweep of the airport, which had to be evacuated.

There were unconfirmed reports on Friday night that the CS gas may have been discharged by a passenger before check-in. The incident is not believed to be terrorist related.

Around 500 passengers and staff were ordered to leave the terminal following an alarm just after 4pm on Friday.

Two casualties were taken to hospital and 25 were treated at the scene for breathing difficulties after the incident, the London Ambulance Service (LAS) said.

In addition, all flights to and from the airport were halted during the investigation and some incoming planes had to be diverted to other airports.

A statement posted to the airport’s Twitter account said: “We apologise to passengers for inconvenience caused today when an alarm was activated, triggering a full evacuation of the airport terminal.

“Passengers were evacuated safely and we thank them for their patience. Following the evacuation, some individuals reported feeling unwell and were treated at the scene by LAS.

“Emergency services responded to evacuation, citing a possible chemical incident. Firefighters and police officers jointly conducted sweeps of the airport building.

“The search of the airport led to the discovery of what is believed to be a CS gas spray".

“The airport was declared safe and reopened at approximately 7pm. Passengers are advised to contact their airline for the latest information regarding their flights.”

A spokesman for the Metropolitan Police said: “At this early stage officers are investigating whether it may have been discarded by a passenger prior to check-in".

David Morris said he had been at the check-in desk for his BA flight to Edinburgh when he began coughing.

"We were queuing up and we were just about to check our bags in, and I was talking and started to cough to the point I was not able to keep talking," the 28-year-old told the Press Association.

"It was getting quite bad and we saw other people starting to cough at the same time. The people behind the desk were coughing the most and quite aggressively.

"Within two minutes, they shouted for everyone to get out."

Mr Morris said BA staff behind the check-in desk jumped over to escape, calling the situation "quite scary".

He said that whatever was causing people to cough did not smell or have any colour to it.

"Everyone was shouting and rushing towards the door," he added.

A London Fire Brigade spokesman said "two complete sweeps of the airport building" were carried out jointly by firefighters and police officers wearing protective equipment.

He added: "No elevated readings were found and the building was ventilated, searched and declared safe."

Medics trained to treat people in hazardous situations also attended the scene.

More than 30 British Airways flights to and from the airport were cancelled, and others heavily delayed.

The closure of the airport came at the worst possible time for the airlines and their passengers: a busy Friday afternoon, when planes are normally heavily booked. Alternative flights from Heathrow, Gatwick and Stansted have few seats available.

BA told passengers: “London City airport has been evacuated this afternoon and our flights will experience some disruption as a result.

“We are awaiting for more information from the fire service, police and the airport authorities at London City and are keeping the situation under review.

“If your flight is still operating please allow plenty of time to travel to the airport as transport to and from the terminal is heavily congested.”

Because the delays and cancellations are due to “extraordinary circumstances”, passengers are not entitled to cash compensation.

But airlines are responsible for providing meals and, if necessary, accommodation, until disrupted passengers reach their destinations.

The Press Association contributed to this report.