A local marine insurer is investigating legal action against a grain ship which last month collided with and sank a fishing trawler in Port Lincoln, SA.

Last week the Liberian-registered Grand Rodosi, which sideswiped and sank the tuna boat Apollo S when it entered Port Lincoln Harbour on October 8, was allowed to leave port.

Associated Marine Insurance CEO Steve Ford says the long process of “ascertaining who owes who and what” will now begin.

“There will be claims and counter-claims,” he told insuranceNEWS.com.au. “It’s not a straightforward legal matter, so it’s really difficult to say how much it will cost.”

Media reports have estimated the damage at more than $28 million.

The Grand Rodosi was originally “arrested” over the accident, but the arrest order was dropped in the Federal Court to allow the ship to depart.

The tuna boat’s owner, Australian Fishing Enterprises, filed documents allowing for the Grand Rodosi’s release.