By Stefanno Sulaiman and Fransiska Nangoy
JAKARTA (Reuters) -Indonesia's coast guard said on Tuesday it has seized an Iranian-flagged supertanker suspected of involvement in the illegal transshipment of crude oil and vowed to strengthen maritime patrols.
A "shadow" fleet of tankers carrying oil from sanctioned Iran, Russia and Venezuela are transferring their cargoes in the Singapore Strait to avoid detection, according to a Reuters analysis earlier this year.
The risk of oil spills and accidents is growing as hundred of extra ships, some without insurance cover, have joined this opaque parallel trade over the past few years.
The Very Large Crude Carrier (VLCC), MT Arman 114, was carrying 272,569 metric tons of light crude oil, valued at 4.6 trillion rupiah ($304 million) and was suspected of transferring the oil to another vessel without a permit, Indonesia's Maritime Security Agency (Bakamla) said.
Bakamla chief Aan Kurnia told reporters the vessel was captured after it was spotted near Indonesia's North Natuna Sea conducting a ship-to-ship oil transfer with the Cameroon-flagged MT S Tinos, on Friday.
The two supertankers tried to escape and authorities decided to focus their pursue on MT Arman, assisted by Malaysian authorities as the vessel sailed into Malaysian waters, Aan said.
MT Arman was also suspected of violating other maritime regulations, such as manipulating its automatic identification system (AIS), Bakamla said.
"MT Arman was spoofing their AIS to show that its position was on the Red Sea but in reality it is here. So it seems like they already had a malicious intent," Aan said.
The MT S Tinos was supposed to have been scrapped in 2018, he added.
The vessel operators could not be immediately reached for comment.
Aan vowed the Indonesian coast guard, with the help of other authorities, would strengthen patrols in its water. Indonesia is the world's largest archipelago with around 17,000 islands.
"We have to be firm, tough. There has to be a deterrent effect so it will not happen again," Aan said.
In 2021, Indonesia seized Iranian- and Panamanian-flagged vessels due to similar allegations. The captains of the two vessels were later put on two-year probation by an Indonesian court.
($1 = 15,155.0000 rupiah)
(Reporting by Stefanno Sulaiman, Fransiska Nangoy; Editing by Martin Petty and Lincoln Feast.)