Two Connecticut fishermen were sickened Sunday after they discovered about ten old military canisters while dredging for clams about 45 miles south of Long Island. As they were throwing the canisters back into the ocean, one of them broke open and exposed a fisherman named Costa, who developed blistering on his arm and leg several hours later. New Bedford fisherman Kevin O'Sullivan told WBZ-TV in Boston the canisters had the date "1914" or "1918" on it, and there's speculation that they may be WWI-era mustard gas.

Captain Kieran Kelly of the E.S.S. Pursuit returned to New Bedford around 4 a.m. Monday so Costa could get medical attention; he was later transferred to Massachusetts General Hospital for further treatment after his condition worsened, the AP reports. The Pursuit went back out to sea, but returned around 9:30 a.m. when a second crew member reported feeling lightheaded. Captain Kelly took her out a third time, but after learning of the incident, the Coast Guard issued a rare "captain of the port order," which commanded the boat to return to port.

The Pursuit is currently anchored south of New Bedford under quarantine. "There's a 500-foot radius around that ship that no one can go to, except us," Captain Kevin Morris of the Marine Strike Team tells CBS2. Captain Kelly has refused to leave the Pursuit during the investigation, even though he says, "My eyes are quite sore; I wash my eyes every few minutes. There's burning on my face, cheeks and hand." Coast Guard spokesman Jeff Hall said earlier that the canisters may have contained mustard gas, but when pressed declined to confirm that speculation. The second fisherman was treated and released.

It's not unheard of for New Bedford fishing ships off of Block Island Sound to drag up military hardware. In Joseph Mitchell's Up in the Old Hotel, the author describes multiple instances of mussel draggers catching aerial depth bombs that became stuck in the mud after being dropped by Army and Navy aircraft during WWII. (They were dropped during the war targeting German submarines.) According to Mitchell, the bombs were dragged up for years after the war, and several fishermen were killed after a bomb brought up in their net exploded.