California city streets covered in sea of foam

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A city in California suddenly found its streets swimming in a mysterious sea of foam.

From a distance, it looked like San Jose had been hit by an extremely localised snowstorm. However, the foam had actually originated in a hangar at the city's Mineta International Airport.

The incident, which happened shortly before lunchtime on Friday, left nearby cars submerged and emergency services with a big clean-up operation on their hands.

The San Jose Fire Department reported that the airport's fire alarm malfunctioned. The system is designed to fill the hangar with foam to suppress a fire, so when it went off it simply flowed out of the open doors and into the streets.

Authorities confirmed that the foam was not dangerous to people, but recommended people stay away as it could irritate their eyes.