A man who told his friend he hooked a 'huge' fish moments before being dragged underwater is still missing 4 days later

• Authorities are searching for a 63-year-old fisherman that was dragged overboard by a large fish.
• His friend said Mark Knittle said, "the fish is huge," before disappearing, miles off shore.

Authorities are nearing the end of their search for a 63-year-old man after he fell into the ocean on Sunday moments after hooking a "huge" fish off the coast of Hōnaunau, Hawaii.

Hawaiian police said Mark Knittle, who is about 5 feet, 10 inches tall and 185 pounds, was fishing for ahi tuna with a friend approximately four miles beyond the Hōnaunau Boat Ramp when he disappeared.

"The friend heard Knittle say, 'the fish is huge,' then saw Knittle go overboard into the water," according to a press release. His friend tried to grab his line but Knittle quickly disappeared; the friend jumped into the water to search but couldn't find him, the news release said.

Ahi, also referred to as Yellowfin tuna, can weigh up to 400 pounds and grow to be as long as six feet, according to NOAA Fisheries. Deep sea fishing experts told Insider that standard tuna weigh about 130 pounds, and anything over 200 pounds is considered "big."

"If there's a fish that's actually pulling him around, you don't know where he could go," Darwin Okinaka, Hawaii County Fire Department assistant chief of operations told The Associated Press.

"When hooked, Ahi tuna usually do not jump, but they will make sudden sideways turns and swim in large circles," Whipsaw Sportfishing, a charter fishing company based in Oahu, said on their website. "Considering their weight, this can be an exhausting experience, and you will have to have patience while trying to reel them in."

According to the press release, the Coast Guard and the Hawaii Fire Department have committed to continuing the search for Knittle for 72 hours — meaning the search will conclude on Thursday.

Brian Wargo, a captain at Bite Me Sportfishing, told Insider that he saw helicopters circling the waters while he was surfing this week, presumably searching for Knittle. He added that the case is being discussed among other fishermen in Hawaii.

"If you don't have your gear right, or you get your hand wrapped in that line, those fish are all muscle," Paul Appleblom, owner of Kauai Apex Charters, told Insider. "I've been trying to even figure out what the hell happened with this guy."

"If you're hand-lining and wrapping your hands incorrectly, you could get pulled over and be along for the ride, and they're strong," he added.

Appleblom told Insider that while deep sea fishing is inherently risky, such overboard incidents are rare.

In 2017, a young man was dragged off his boat near the coast of Australia after having caught a large marlin fish. He remained in the water, entangled with the fish, for roughly six hours before he was rescued, according to BBC.

"These fish are fighting for their lives, their adrenaline is pumping. They're in survival mode," Appleblom said. "Anything can happen."

The Hawaii Police Department and the Coast Guard did not immediately respond to Insider's request for comment.