Footage has emerged of a ship pumping tuna blood into the sea off Buġibba, as the controversy over the tuna pens rages on. 

The footage was shot from a rhib near the tuna pens at Sikka l-Bajda yesterday, but the operators insisted they were within the law.

The liquid was being pumped from four separate hoses in the sides of the ship, two on the port side and two on the starboard side. The boat, Lady Tuna, belongs to Azzopardi Fisheries. 

"On approaching the ship the liquid was identified as raw, untreated tuna blood which is being pumped continuously into our bay in addition to the tuna carcass and waste which is being dumped and is starting to wash up ashore," Nicolai Abela told timesofmalta.com, who added that the workers switched the blood flow pumps off when they realised they were being filmed. 

"This is an assault on our environment," he said. 

But when contacted, Aquaculture Federation secretary John Refalo insisted the tuna vessels were not doing anything illegal.

"The blood always goes back in the sea, the offal doesn't," Dr Refalo said. 

But Mr Abela hit back, saying the least the operators could do is shift the tuna vessels further away from shore and spare bathers from seeing the gruesome process. 

The video emerged a month after the operators of four tuna fish farms were served with an emergency enforcement order, hours after it emerged that more than half of the fish farm cages are illegal.

A revised legal notice has been published which will introduce harsher administrative fines intended for any planning illegalities related to the sea including illegalities in the aquaculture sector. Daily fines will go up to €2,000, up to a maximum of €200,000 in the aggregate.