London City Airport
Hundreds of people were evacuated from London City Airport following the incident Twitter/@Shaunaa

A 25-year-old man has been arrested in connection with a chemical incident involving CS gas spray at London City Airport which left dozens of people with breathing difficulties.

Two people were hospitalised and a further 25 treated at the scene following reports of people being unwell at the airport on 21 October.

The airport was evacuated and closed to all outgoing and incoming flights after the fire alarm was set when passengers and staff began "coughing uncontrollably".

Following a search of the area, police uncovered CS gas spray, which is normally used for self-defence and to control crowds.

The suspect has been arrested on suspicion of "using a noxious substance to cause serious damage" an offence under section 113 of the Anti-Terrorism, Crime and Security Act 2001.

He was detained at an address in east London and has since been released on bail until November pending further enquires.

The closure of the airport disrupted flights for several hours, with many getting diverted to other airports, while emergency services dealt with the chemical indecent.

A Met Police spokesperson said: "Police arrested a man on Saturday, October 22 in connection with an incident at London City Airport on Friday, October 21.

"The man, 25, was arrested at a residential address in east London and taken to a west London police station. He was arrested on suspicion of using a noxious substance to cause serious damage –an offence under section 113 of the Anti-Terrorism, Crime and Security Act 2001.

"He has since been bailed pending further enquiries to a date in late November."