A freighter involved in a fatal accident has been seized off the coast of West Africa with cocaine worth £155million on board.

Much of the stash found on the Panama-registered Opnor off Senegal was headed for Britain.

A heavily-armed Spanish special forces team discovered 3.7tonnes of cocaine below decks.

The 150ft-long Opnor's Dutch master and mate were arrested along with four Ghanaian crew.

The Opnor should have been scrapped five years ago after being involved in an accident in the port of Lerwick, in the Shetland Islands, in which a Polish seaman was killed.

But it ended up in the Caribbean where it was bought by the drugs barons.