Steve Bruemmer suffered a broken femur as a result of the attack. One of his rescuers said his leg was almost "severed". Photo / Facebook
A swimmer has miraculously survived a gruesome shark attack that left him with "severe injuries" after three bystanders came to his rescue.
Steve Bruemmer, a retired IT specialist, was swimming at Lovers Point Beach, in Monterey Bay, California, when the shark launched at him this week.
Sacramento Police officer Paul Bandy and his nurse wife Aimee Johns were paddleboarding at the popular cove when they heard screams for help and noticed a man in distress.
"He was screaming for help, you could tell the sound and the emotion in his voice that there was something definitely wrong and he was slapping the water," Bandy told KSBW.
"I wasn't sure if that was some sort of thing he was trying to get something away from him or just trying to draw attention to himself.
"As soon as we got close to him, we could see he had severe lacerations on his arms and legs."
Johns told KSBW that when they got the victim to shore, they cut off his wet suit and applied tourniquets to his limbs and abdomen. He was "bleeding severely," she added.
Local resident Heath Braddock was teaching children to surf in the area when he also noticed the commotion.
Braddock told the programme when he heard Bruemmer's cries he "grabbed a couple boards and took two boards out".
"As I approached, I saw kind of the pool of blood. It was probably the size of a table or a car," he told KSBW.
The three rescuers pulled the victim onto the board and brought him back to shore, Johns getting in the water to propel the board from behind.
"We got my biggest board and the gentleman, Paul, helped me roll the victim on the board belly down and got him kind of centred and stable," Braddock said.
"We had him hold my food and we paddled him in."
When they got back to the beach, "his leg was almost severed," according to Johns.
Bandy added: "Severely injured. All the way down to the bone."
Bruemmer, a resident of Monterey County who is part of a swimming club that frequents Lovers Point, was transported to Natividad Hospital by American Medical Response.
Ocean Grove Police Department confirmed they responded to reports of a shark attack around 10.30am local time and found a male swimmer with "significant injuries".
He sustained a broken leg in the attack as well as severe wounds to his stomach, shoulder and leg, police reported.
"We want to express our gratitude and appreciation to the good Samaritans that took immediate action and personal risk to assist the swimmer," Pacific Grove officers said in a statement.
"We send our prayers and thoughts to the swimmer and their family."
A firefighter drone was deployed in an attempt to locate the shark after the attack. Pacific Grove city manager Ben Harvey told the Monterey Herald that the shark was spotted in the area after the attack. There have not been any reports of further sightings since.
While shark attacks are rare in California, another Sacramento-area resident Tomas Butterfield, 42, was killed by a shark several kilometres south in Morro Bay on Christmas Eve.