Police say a mystery haze which swept in across the south coast has now dissipated.

Kent Police yesterday warned people on the south coast to close their windows as a chemical haze blew in from the sea in neighbouring Sussex.

Up to 150 people have been affected by the mist, with irritation caused to eyes, mouth and throats.

The first cases were near Birling gap in East Sussex, but the warning for Kent was made as the haze spread towards Eastbourne and then Hastings, nearer the county's border.

Scroll down for video of the moment the haze hits the beach

Kyle Crickmore, who took the picture above and filmed the video below, said there was a strong smell of chlorine in the air and people's eyes were streaming.

Others described it as a 'weird gas leak.'

A Sussex Police spokesman said today: "While the nature of the gas hasn't been established, East Sussex Fire and Rescue Service has advised that it is 'extremely unlikely' that it was chlorine, as was being suggested on social media.

"The effects, while uncomfortable, were not serious and an investigation is now under way by a number of agencies working in partnership to establish the source of the gas.

"It is believed that it came in from the sea, but this has not been confirmed and work continues to locate the cause."

Video by Kyle Crickmore

Sussex Police have confirmed the haze appears to have come from the sea, but the source has not yet been established. An officer described it as an 'irritant gas.'

Neither the gas nor its source had been identified today, but agencies are continuing to investigate and have not ruled out either on-shore or off-shore locations.

It does appear that it swept in from the sea driven by on-shore breezes. However, weather models suggest that an onshore source in northern France is very unlikely.

While reports of those seeking medical treatment have now dwindled away, anyone still suffering the effects are advised by Public Health England to irrigate their eyes if they are irritated and to wash any other irritated areas with plenty of soap and water.

Coastguard rescue teams from Birling Gap, Eastbourne, Bexhill and Newhaven were yesterday involved in clearing the beaches in the area.

Steve Carson, commander with the UK Coastguard, said: ‘We are working with the other emergency services in the area to help all those affected. Our Coastguard teams are out clearing the beaches. Please help us by leaving the beach if you are asked to.’

"This seems to have been caused by an unknown haze coming in from the sea, but the source has not yet been established."