Scores of seabirds have been rescued after being found covered in some kind of oil along the North East coast, including Northumberland, the RSPCA has said.
The charity started receiving calls about birds covered in a black, oily substance on Sunday.
The birds – more than 20 now – have been found by the public at various locations from Amble down to Redcar, in North Yorkshire.
The source of the oily substance has not been identified.
RSPCA inspector Jaqui Miller said: “We have been collecting seabirds from several different places up and down the coastline after members of the public spotted them.
“Guillemots, puffins, razorbills and gulls have been affected. The first ones to come into us were of a good weight and alert but some of the ones coming in recently have been less so and very sadly a couple of them have not made it.
“We don’t know what the substance is, or where it’s coming from, but the birds are covered in it.
“We’re getting them to local vets where they are being rehydrated and stabilised then they are being taken to our specialist wildlife centre in Cheshire.
“The birds will be cleaned hopefully to remove the oil from the feathers, which will mean they can remain waterproofed when finally released.
“If you come across a seabird you think is affected, contact us on 0300 1234 999.”