The man, who is the captain of the ship, is being held, among other things, for using a false document, a felony.
"The man is suspected of having presented and referred to several suspected false maritime certificates when the Coast Guard searched the vessel," says senior prosecutor Adrien Combier-Hogg in a press release.
He is also suspected of violating the Maritime Act and the Ship Safety Act.
The man is being questioned along with others involved, and the relevant documents are also being examined, the prosecutor says.
Last Friday, the police's national task force and the Coast Guard, in the joint operation "Black Coffee," boarded the ship off the coast of Trelleborg.
Following an on-board inspection, the Swedish Transport Agency issued an international ban on use of the ship on Sunday. This means that the ship is not allowed to leave anchorage until the deficiencies have been addressed.
The Swedish Transport Agency has not yet received any feedback from the shipping company. The agency's press service states that it is awaiting word that the deficiencies have been addressed. Only when that has been received will the agency board again and check whether the ban on use can be lifted.
"So far, the crew on board is doing okay," wrote the Swedish Transport Agency's press officer in an email.
The ship is reportedly on Ukraine's sanctions list and is suspected of transporting stolen grain. It is anchored in Swedish waters off Trelleborg.
