Two fishermen in Mexico caught a 2,000-pound (900-kilogram), 20-foot great white shark on Sunday -- one of, if not the, the largest fish ever captured. The two fishermen initially thought they caught a school of smaller fish, and were surprised when they brought up their net and the shark, already dead, was in it.

We were amazed and immediately realized that we had a huge, dead, great white shark, and then we thought 'what are we going to do?' Guadalupe, one of the fishermen, said, according Pisces Sportfishing.

The two fishermen hitched the shark to the boat and towed it back to shore, where 50 people had to help pull it on land.

Though catching a great white shark, especially one this large, is exceedingly rare, fishermen often bring in fish weighing over 1,000 pounds (450 kilograms). Click through the slideshow to see some of the biggest fish ever caught.

Mekong Cat Fish
This Mekong giant cat fish, caught on May 1, 2005 by fishermen in Thailand, is the largest freshwater fish ever caught. The fishermen struggled with the fish for over an hour trying to get it on board the boat and when they finally succeeded, the fish measured 9 feet long (2.7 meters) and weighed in at 646 pounds (293 kilogram). The fish was nicknamed the “grizzly bear” catfish, since it weighed just as much as one.The Mekong giant catfish is critically endangered, and the fisherman tried to keep it alive. Unfortunately, the fish died and was later eaten by local villagers. Suthep Kritsanavarin
Swordfish
A fisherman caught the largest swordfish ever on May 7, 1953 using only a rod and reel. Lou Marron caught the fish off the coast of Chile after a two hour battle. The fish was almost 15 feet (4.5 meters) long and weighed 1,182 pounds (536 kilograms). The fish is currently on display at the International Game Fish Association Fishing Hall of Fame & Museum in Miami, Fla.Lou Marron wasn’t the only angler in the family -- his wife, Eugenie Marron, set four records of her own, including the largest swordfish caught by a woman. She caught the fish, which weighed in at 772 pounds (350 kilograms), exactly 13 months after her husband’s record setting catch. International Game Fish Associ
Atlantic Bluefin Tuna
Ken Fraser caught a 1,496-pound (678 kilogram) Bluefin tuna off the coast of Nova Scotia in 1976. Using only a rod and reel, Fraser caught the fish in 45 minutes. It remains the largest Bluefin tuna ever caught. Fraser set out looking for the largest tuna, and wrote a book about his search and the ensuing catch called “Possessed.” He now works as a guest speaker for a variety of fishing shows and seminars. Ken Fraser
Pacific Marlin
Marlin are a prized fish because of the degree of difficulty involved in catching one -- fish weighing upwards of 1,000 pounds are common and they are known to put up a fight. The largest marlin ever caught was a 1,805-pound (818-kilogram) fish caught off the coast of Hawaii in 1970. Known as “Choy’s Monster” after the man, Cornelius Choy, who caught it, the fight lasted for hours until the fish was finally reeled in. The fish initially weighed in at over 2,000 pounds, but was found to have a 155-pound yellowfin tuna in its belly. BigMarineFish.com
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