LONDON (AP) — More than 100 people have been treated for streaming eyes, sore throats and breathing problems after a chemical haze spread over a stretch of the southern England coastline.

The emergency services say they are working to establish the origin of the mist, which sent people fleeing from the beach and cliffs at Birling Gap, a coastal beauty spot about 60 miles (100 kms) south of London.

Life boats were dispatched to help clear people from beaches, and Eastbourne District General Hospital said it had treated more than 130 people after Sunday's incident.

The cause of the haze has not been determined. Pollution has been known to drift to Britain from industrial units in France.

Sussex Police said Monday that "this was an isolated incident and is not expected to recur."