British Divers Marine Life Rescue (BDMLR), an internationally recognised voluntary marine animal organisation, is searching for the whale in a bid to free it.
The images were shared by the Forth Marine Mammals group on social media, drawing several concerned comments.
Claire Sandilands said; “Wow - someone did think there was something unusual in the water behind the whale when we saw it in Kinghorn! They obviously had eagle eyes! Hope that it has broken free by now.”
Jenny McNeill said: “Hopefully it’s either managed to get free or a positive sighting tomorrow and they can get her free.”
Crowds flocked to see the whale and its calf off the coast of Kinghorn, Fife, on Wednesday.
The pair were seen just a few hundred yards from Pettycur Harbour.
Humpback whales can grow to more than 40ft in size and their presence off the Fife coast in the early months of 2017 and 2018 drew plenty of visitors.
The Evening News is awaiting a statement from BDMLR on the matter.
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