A 41-year-old man was killed on Monday after a shark bit off both of his legs while he was surfing off Australia's east coast.

Officials said that the Japanese surfer died at Shelly Beach, a popular tourist attraction near Ballina, about 116 miles south of Brisbane.

"We can confirm the man is a Japanese national, aged 41," Detective Inspector Cameron Lindsay told the local Northern Star newspaper, according to AFP. "He's been living in the Ballina area for around 12 months."

The unnamed man was sitting on his board waiting for a wave when the shark attacked him from behind, grabbing the back of the board and the man's legs, said David Wright, mayor of the New South Wales town of Ballina. The man's friends, who had been surfing alongside him, then helped get him out of the water and administered first aid. However, "because both legs were gone, he bled to death very quickly," said Wright, report the Associated Press.

"He had leg injuries and they were substantial, they were injuries that led to a significant loss of blood," said Det. Lindsay.

Mayor Wright added that rescuers believe a great white shark was responsible for the attack.

"For a shark to take the board and the person sitting on it, it's got to be very big," he said.

According to a local cafe owner, identified as Karen, the shark came from nowhere.

"It just came up between a bunch of surfers," she said. "They weren't even that far out. He lost both his legs."

Officials closed beaches in the area following the fatality.

The incident occurred just one day after Jabez Reitman, 35, was attacked while sitting on his surf board off Seven Mile Beach near Byron Bay, about 30 kilometres north of Ballina.

"Something just jumped out of the water and just grabbed me at my hip and dragged me off my board and took me under the water," he told the Australian Broadcasting Corporation.

He managed to paddle 60 meters back to shore, however he suffered from a cut to his back and puncture wounds to his buttocks.

"I just freaked out," Reitman told reporters on Sunday. "I thought it was a dolphin at first until I started feeling and realized it was pretty significant lacerations."