A woman is feared dead after being taken by a crocodile during a late-night swim in far north Queensland in what has been described as an avoidable tragedy.

Cindy Waldron’s friend Leeann Mitchell tried to drag her to safety after she was pulled under water as they swam at Thornton Beach in the Daintree National Park on Sunday evening.

But local federal MP Warren Entsch says they shouldn’t have been swimming there at that time of night.

“This is a tragedy but it was avoidable,” Mr Entsch told AAP on Monday.

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“If you go swimming at 10 o’clock at night, you’re going to get consumed.”

He went so far as to describe it as an act of “human stupidity” and says he hopes it doesn’t spark a “hysterical debate about crocodile management”.

Police and SES volunteers conducted a large-scale land, air and sea search on Monday, but failed to find any trace of New Zealand-born Ms Waldron, 46, who had been living in the NSW town of Lithgow for several years.

Senior Constable Russell Parker said Cairns woman Ms Mitchell put up a valiant fight to save her friend after they ventured into waist-deep water about 10.30pm.

“Her 47-year-old friend tried to grab her and drag her to safety and she just wasn’t able to do that,” he told ABC Radio.

“They had been walking along the beach and they’ve decided to go for a swim … (it was) probably a very nice, clear night, but obviously (they) may not have been aware of the dangers.”

Ms Mitchell managed to make her way back to the shore, where she made a frantic dash to a local business to get help.

She was later taken to hospital for shock and grazes.

Acting Inspector Ed Lukin said on Monday afternoon a five-metre crocodile was spotted in the area on Sunday, before the attack.

The case echoes a fatal crocodile attack near the Daintree River just before Christmas in 1985.

Beryl Wruck, 43, was taken by a five-metre croc after a fateful decision to take a late-night dip in the shallows of Barratt Creek after an evening of dancing and drinking with friends.

More recently, five-year-old Jeremy Doble died when he was attacked by a 4.3-metre crocodile in a swamp behind his Daintree River home.

He vanished in February 2009, with his seven-year-old brother telling police he saw a croc in the water moments after the boy disappeared.

The search for the woman will continue on Tuesday.