Some 17,213 salmon escaped from a net pen in Sognefjord in Gulen, Norway, earlier this month, almost double original estimates.
It's also been confirmed that the escaped fish had tested positive for pancreas disease and were awaiting harvest by processor Slakteriet.
Around 3,000 fish have been captured and the case has been referred to the police.
“After the hole in the net was identified on Monday, September 16, 2019, we have done everything in our power to reduce the magnitude of this deplorable incident," Slakteriet Brekke said in a press release.
"We have assisted and followed the authorities' requirements and started recovery according to our contingency plan."
The three-by-two meter hole is thought to have been made by a boat propeller.