Liberal Democrat Farron, who

"Obviously, we don't want plastic pollution on the beach, but the nurdles can be tainted with other chemicals which can be directly toxic," said Nick Acheson, a conservationist and wildlife ambassador for the Norfolk Wildlife Trust."This is certainly a very bad time of year because it's when [birds such as] oyster catchers and ringed plovers are nesting on our beaches, and when hundreds of thousands of migrating birds are moving along our coast going back to their arctic breeding grounds.

"Our African migrants will also be arriving any time now."The Maritime and Coastguard Agency said it was notified by the Royal National Lifeboat Institution on Sunday after a "sheen" of nurdles was spotted in the sea off The Wash.According to the RSPB, The Wash supports more than 400,000

, the largest harbour seal colony in the UK, and is home to countless rare plants and invertebrates.Members of the public have been warned not to touch the nurdles, and to instead alert the coastguard by calling 999.

The National Trust, which manages nature reserves on the North Norfolk coast, has advised dog owners to

The coastguard said a nurdle "retrieval operation" was under way.Some reports say more than 200 migrants of different nationalities had been detained at a military facility in Wad Madani before the RSF advance - information the BBC cannot independently confirm.

It has since been reported that the detainees were moved with the army when it withdrew from Wad Madani.The UN refugee agency says it has received similar reports about the detention by the army of asylum seekers and refugees. According to the UN, there are more than 147,000 Eritreans and around 70,000 Ethiopians in the country.

It told the BBC it was planning a verification mission to Sennar state, which includes the towns of Sinjah and Rabek, urging relatives of refugees who believe them to be in detention to report the informationLikewise the International Committee of the Red Cross (ICRC) said those with a family member missing in Sudan should open a case via