A POLLUTION alert was issued south east of Fair Isle on Wednesday by the European Maritime Safety Agency.
One of the organisation’s pollution tracking satellites issued a mid-level green alert in the evening, with Shetland Coastguard attempting to contact three nearby vessels to investigate.
However, no pollution was spotted due to the darkness and no further action will be taken.
Meanwhile, a targeting drone believed to be owned by the RAF was found by a member of the public off Heylor in Ronas Voe, on Wednesday.
Shetland Coastguard took advice from Ministry of Defence bomb disposal staff, who confirmed the item was a targeting drone used for training purposes and not an explosive.
A large green buoy was also spotted on Wednesday in Bigton – but it was too dark for volunteers to investigate at the time.
Coastguards hope to be able to recover it on Thursday.