The shark that killed a young surfer off Western Australia yesterday may have been in the area where the fatal attack happened for up to four days.
A search-and-destroy mission is continuing for the great white shark up to five metres long that killed Ben Linden while paddling his surf board in the ocean off Wedge Island, just north of Lancelin, with a friend yesterday morning.
Fisheries Minister Norman Moore said the shark could have been hanging around the waters off Wedge Island since Tuesday.
"The indications are that it has been around for four days and nobody had reported it being sighted," he said.
It has also been reported that surfers had nicknamed the four to five metre long great white shark "Brutus".
Western Australia's Department of Fisheries said beaches remained closed along the popular surfing stretch while a boat scoured the ocean for the shark that killed the 24-yeart-old man.
Mr Linden was surfing with a mate about 100 metres from shore, four kilometres south of Wedge Island yesterday when he was attacked by what was described as a ''massive'' white pointer at about 9am.
Mr Linden was the fifth person killed by a shark off WA's coast in less than a year.
His remains have yet to be recovered.
Fisheries Department shark response unit spokesman Tony Cappelluti said a boat was grid-searching the area with orders to capture and kill the fish.
''At this point in time, we're basically looking for the shark and if there are any remains found we'll involve the police,'' Mr Cappelluti said.
''Permission was given yesterday to capture and destroy a shark if it was believed to have been the one responsible.
''If something is in the four to five metre vicinity and it's a white shark - which is the description we've got from witnesses - you make the assumption that it could be the same shark.''
However, Mr Cappelluti admitted the likelihood of capturing the shark, which was last sighted swimming out into deeper water, was slim.
Baited hooks had been removed from the area on Saturday night and the Fisheries Department was considering calling off the water search at midday today as weather conditions deteriorated.
Local police and volunteers continued to search beaches with quad bikes and four-wheel drives for Mr Linden's remains.
REPORTS OF SHARK SIGHTING SPOOKS SURFERS
About 15 surfers who were in the water near Wedge Island this afternoon scrambled out quickly after a possible sighting of a shark.
Mr Cappelluti from the Fisheries Department said the report had not yet been confirmed but Fisheries officers would investigate it.
"A big group of surfers have just left the water after one saw a dark shadow," he said.
He did however mention that Fisheries officers had reported a pod of dolphins in the area earlier in the day.
He said the possible sighting was believed to have happened after 2pm slightly north of yesterday's fatal shark attack.
"As you can imagine, everyone is a bit spooked," Mr Cappelluti said.
The surfers were in the water despite the beach still being closed.
"The closer of beaches is more of a suggestion, we can't do much if people decide to enter the water," Mr Cappelluti said.
GIRLFRIEND'S EMOTIONAL TRIBUTE
Earlier Mr Linden's girlfriend of eight years, Alana Noakes posted a moving tribute on his Facebook wall.
"I'm devastated to let everyone know that my beautiful man, Ben Linden, was the surfer who was taken by the shark at Wedge this morning...
"Ben was the most amazing man, he lit up the lives of all who knew him.
"He was the most talented, good-natured, beautiful person I've ever met.
"He was the love of my life, my best friend, my rock and my soulmate.
"I, like everyone who knew him, absolutely cherish every moment of the last 8 years I spent with him.
"He has helped me to be a better person, to learn to 'ride the waves' of life.
"Let's remember that he was doing something that meant the world to him. Surfing was his soul, his life, his culture and his passion.
"He loved mother nature in all her glory and is now in her arms eternally. Let's rejoice in that."
According to his Facebook page Mr Linden, a cabinet maker, had a passion for surfing and music and had been in a local band called Fools Rush In.
His family has asked for privacy but expressed their gratitude to the emergency services and volunteers that have assisted in the search for their son.
- WA Today with AAP