Several Middletown volunteer firefighters suffered minor injuries including heat exhaustion.
No one was hurt but the road near the cooperative remained closed on Wednesday.
The cause of the blaze, which broke out just after noon near the Belford Harbor marina, remained undetermined, fire officials said.
The fire broke out in a marshy part of Middletown along Port Monmouth Road, at the Belford Seafood market, Belford Harbor Docks and across the water from the Belford ferry terminal.
Witnesses said the fire was up to 300 feet in length. An estimated 200 lobster pots were destroyed, according to fire officials.
David Tauro, manager of the Belford Seafood Co-op, told Patch that he thinks the fire was 200 to 300 feet in length. He watched as at least two boats were consumed by flames.
A video of the fire was posted on the Seaford Cooperative's Facebook page here:
"Everyone is safe. The store at the co-op are open. Unfortunately the road is still closed. I will keep you guys posted," the cooperative said on its Facebook page on Wednesday.
"I'm coming down East Road and all I see is this big black cloud of smoke. As I got closer and pulled in I couldn't believe how much fire was there," Tauro told Patch.
"People were yelling, 'Fireworks are going off!' but it was actually power lines hitting the concrete," Tauro said. "You could see all the sparks going off."
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