Only two of the four vessels detained by the Indonesian authorities in separate incidents in recent weeks were Singapore-registered, said Singapore's port authority.
Earlier reports had suggested that all four vessels were flying Singapore flags and the four people detained were all Singaporeans. This is not true, said the Maritime and Port Authority of Singapore (MPA) yesterday in response to media queries.
A Singaporean, who was one of the four people held, has since been released, it added.
The first incident reported on March 5 had involved two vessels - Singapore-registered DM 55 and Belize-registered Sea Sparrow 1.
The Indonesian authorities nabbed the vesels, which allegedly had no permits, when they were piloting a tanker travelling through Indonesian waters in the Malacca Strait. Such boats are typically used by big vessels to navigate through crowded waters.
The Singaporean, a marine surveyor who was detained following the incident, returned home on Monday after the Singapore Consulate in Batam stepped in to help, MPA said.
In another incident four days later on March 9, the Indonesian coast guard detained two vessels off the resort island of Batam for allegedly sailing in those waters without proper documentation.
The two vessels were ASL Glory, which was flying a Singapore flag, and Indonesia-registered AST 1837, said MPA.
Indonesia has been stepping up sea enforcement activities after President Joko Widodo pledged to get tough on those trespassing into Indonesian territory.
Singapore's port authority, which is assisting the Indonesian authorities in their investigation of the incidents, said it has reminded the Singapore shipping community that all vessels should follow international best practices and adhere to the relevant coastal state laws.
This article was first published on Mar 21, 2015.
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