Shadow Home Affairs Minister James Paterson has hit out at Australians praising Hamas leader Yahya Sinwar after he was killed in an Israeli strike.

Demonstrators at a pro-Palestine protest in Sydney on Sunday were seen celebrating the life of the now-deceased terrorist leader.

Mr Paterson warned Australia had entered a “law enforcement crisis” after a failure to deter protesters.

“It is the failing to enact meaningful consequences for repeated instances of behaviour like this over the last year that has led extremists in our country to become emboldened and openly defy the law,” Mr Paterson told Sky News host Chris Kenny.