A 16-year-old boy who lost a leg following the second shark attack in three days along the Florida Panhandle was in critical condition Tuesday and doctors were hoping he hadn't suffered any brain damage from the blood loss.

Craig Adam Hutto, of Lebanon, Tenn., survived the attack Monday but his leg was amputated.

Dr. Reed Finne, a cardiovascular surgeon at Bay Medical Center in Panama City, said Tuesday that Craig's leg suffered irreparable damage to blood vessels and nerves between the hip and knee, as well as to most of the surrounding muscle.

Finne said it was too soon to tell if the teen suffered any brain damage from blood loss. In 2001, a 9-year-old Mississippi boy, Jesse Arbogast, suffered severe brain damage from blood loss when a shark tore off his arm as he swam near Pensacola.

"We're hopeful. He's young, he's healthy. He should be OK, but he's still sick," Finne said of the boy.

Strikes {{{80}}} miles apartHutto was fishing in waist-deep water about 60 feet from shore with his brother and a friend on Monday when the shark grabbed him in the right thigh, nearly severing the leg.

Three days before the attack on Hutto and about 80 miles away near Destin, 14-year-old Jamie Marie Daigle died from her injuries after her leg was mutilated by a bull shark.

The attack on Hutto was witnessed by Karen Eaker, 42, of Horn Lake, Miss.

"Within five seconds it was obvious there was something wrong," Eaker said. "We had heard the word 'shark' and then we saw the red water and the tug-of-war going on between the brother and the shark."

Nearby, Bill Pascoe, of Jacksonville, was scooping up shells with his 5-year-old son when they heard a commotion. As he got closer, he saw blood in the water.

"One man jumped in and kind of looked like he had it in a head lock and was punching it on the head to get him to let loose," Pascoe said.

A doctor who happened to be nearby began treatment once the teen was ashore. He was then taken to Panama City's Bay Medical Center, where the leg was amputated. Craig's family members, including the brother who was with him in the surf, declined comment at the hospital.

Gulf County's Board of County Commissioners issued a mandatory closure for beaches in the county until midday Tuesday. Destin-area beaches reopened Sunday.

More attacks in summerThe number of shark attacks rise in the summer because the animals come closer to shore to search for food, said John Tyminski, a senior biologist with the Center for Shark Research at Mote Marine Laboratory in Sarasota.

"I don't think there is any reason to come to a conclusion that this is strange," Tyminski said of the two recent attacks.

Daigle, of Gonzales, La., had been swimming with a friend about {{{100}}} yards from shore in neighboring Walton County when a shark bit her in the leg. Paramedics and an air ambulance crew were unable to revive her.

Florida averaged more than 30 attacks a year from 2000 to 2003, but had only 12 last year, said George Burgess, curator of the International Shark Attack File at the University of Florida in Gainesville. He attributed the drop to the four hurricanes that hit Florida last year, keeping residents and visitors away from beaches.