Only local residents and landowners have keys to the crossing

Network Rail says the crossing, near Bangor, has become unsafe because the workers cannot speak good enough English to talk to signalling staff and cross safely.

The crossing has now been locked so that only local people can use it.

The rail company says there is a footpath crossing nearby which can be used as an alternative.

The level crossing at Abergwyngregyn was being used by cockle pickers to drive to cockle beds on the Lafan Sands.

But it is only supposed to be used by local landowners and farmers.

They telephone the signal operators who tell them if it is safe to cross, before they can then drive over.

But Network Rail says some of the Chinese cockle pickers could not speak enough English to be told when it was safe to cross.

The crossing should only be used by local landowners and farmers

They said that there was one worker who could speak English, but he often arrived too late for the whole group to cross safely.

As a result the crossing has now been locked, with only local residents and landowners being issued with keys.

Last month, Abergwyngregyn was the scene of a police operation in which 14 cockle pickers, thought to be Chinese, were arrested on suspicion of being illegal immigrants.

The 14 arrests were made as the cocklers left Lafan Sands.

Police staged the operation to check that those doing the cockle-picking had licences to do so.

Police officers set up road blocks near the A55 exit, and a police helicopter was also used in the operation.

It has now been revealed that all 14 workers had claimed asylum - one in another unknown country.

Network Rail has stressed their decision is not connected to these arrests and is based only on safety grounds.