SHARK nets protecting some of Sydney's most popular beaches are being sabotaged, leaving surfers and swimmers vulnerable.
Activists are accused of vandalising shark nets at Queenscliff, Bondi, Dee Why, Manly, Curl Curl and other busy beaches across Sydney, the Daily Telegraph reports.
Since 2015, there have been 22 shark attacks in New South Wales.
Four deadly sharks were caught in the first month after shark nets were laid. There have been no attacks since that time, and only one fatal attack at the 51 netted beaches between Newcastle and Wollongong since 1937.
The most recent vandalism occurred in October, when the shark net at Queenscliff was cut.
The Bondi shark net was "slashed down the middle" about 12 months ago, leaving swimmers at risk until it was repaired.
The vandalism was revealed through a Baird Government report on shark nets.
The same report found one-in-three animals caught in the nets did not survive the encounter.
Sharks represented 20% of the by-catch, and more than half of those died, including four great hammerhead sharks, listed as vulnerable under NSW environmental law.
A bottlenose dolphin -- protected under state law -- died in the nets off the coast of Lennox Head.
It is understood that NSW shark nets have been vandalised at leat 20 times since 2010.
Primary Industries Minister Niall Blair slammed the mindless eco-vandals on Monday, saying: "Deliberate acts of malicious damage are not just dangerously foolish, they can attract sentences of up to five years jail under the Crimes Act."
Opposition MP Walt Secord said the acts put "thousands of families and tourists in harm's way."
"These cowards may try to describe themselves as 'eco warriors' but they are nothing but 'eco cretins'.
"If the government is considering tough measures to target these fools, I am on board and I will raise them with my shadow cabinet colleagues."
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