Germany’s Hamburg Airport was evacuated Sunday morning after a number of passengers and staff complained of irritated eyes and breathing difficulties, leading to 68 people being treated by the emergency services.

Reports of a possible toxin being released in the airport through the air conditioning system circulated on Sunday, with the local tabloid the Hamburger Morgenpost reporting the agent may have been a pepper-spray. The paper reports several people called the emergency services after a bad smell went through the airport, causing several people to experience coughing, irritation of the respiratory system, and burning eyes.

The whole airport was evacuated, with passengers stuck outdoors in freezing conditions without shelter while the emergency services assessed the situation in terminals one and two.

All flights were halted for several hours due to the evacuation, airport spokeswoman Karen Stein said.

“We have cancelled all flight at least until 2 p.m. (1300GMT) and most parts of the airport have been evacuated,” she said.

Some 68 people were treated by the emergency services at the scene, and a total of nine were taken to hospital. A fire brigade spokesman said a pepper spray cartridge was found in a passenger area, which was beleived to have been discharged into the air conditioning system.

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