SAN JUAN, Puerto Rico (AP) — U.S. authorities have seized a haul of marijuana from a Guyana-flagged cargo ship in the Caribbean Sea south of Puerto Rico, officials said Monday.

At a news conference in the U.S. territory’s capital of San Juan, U.S. Coast Guard Capt. Robert Warren said the vessel An Nurl was stopped last week some 200 miles southwest of southern Puerto Rico.

A boarding team found 3,591 pounds (1,630 kilograms) of pot hidden on the cargo vessel, he said. The haul was estimated to have a value of $3.5 million.

Five Guyanese crew members have been detained for prosecution.

Guyana media say the ship was registered to a local businessman and apparently carried rice between the South American country and Jamaica.

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