Six suspected pirates operating in the Malacca Straits were caught by Western Fleet Quick Response Team from the Indonesian Navy's Tanjung Pinang base on Monday in Batam waters in Riau Islands.
The group was suspected of plotting attacks on tankers passing through eastern Malaysia.
The Tanjung Pinang Navy base commander, Comm. S. Irawan, said the arrest came about following a tip-off from an informant with information about criminal activities in the Malacca Straits.
"The team followed it up by intercepting the group at sea," Irawan said. The team managed to detain the boat, which had the six suspects on it. From the six, three are known to have engaged in piracy.
"During questioning they said they wanted to attack ships in Malaysian territory," he said.
The six have been identified as: Piyan Sinaga, the boat owner, Angki, the skipper, Feri S. Lubis, an assistant to the skipper, and Udin Ali, Teguh Adrianto, and Riswan, crewmembers.
Irawan said Udin Ali had a piracy record stretching back to 2012 and had been sentenced to four-and-a-half years in Tanjung Pinang prison for piracy. Teguh also has a record.