Malaysia Pursuing Oil Tanker Hijacked by Pirates off the Coast of Vietnam

The Malaysian navy is negotiating with armed pirates aboard an oil tanker near Vietnam, with naval authorities reportedly in direct communication with the ship's captain who was commanding the vessel before it was hijacked last week.

There are at least eight pistol and machete-wielding pirates holding the MT Orkim Harmony hostage, reportedly speaking in Indonesian accents, navy chief Abdul Aziz Jaafar said. Malaysia's maritime agency detected the vessel off southern Vietnam on Wednesday, noting that the pirates had given the ship a new look, repainting it black from its original blue and rebranding it as the Kim Harmon.

Related: Pirates Are Running Wild and Hijacking Oil Tankers in Southeast Asia

MT Orkim Harmony: At least 8 perpetrators are onboard. They are armed with pistols and 'parangs'. They speak with Indonesian accent.

— Abdul Aziz Jaafar (@ChiefofNavy)June 18, 2015

MT Orkim Harmony: The vessel is under surveillance and being photographed by the RMN's Super Lynx — Abdul Aziz Jaafar (@ChiefofNavy)June 18, 2015

The official said the captain and all 22 crew members were safe on the ship, which disappeared on its way to Kuantan in northern Malaysia on June 11. There are 16 Malaysians, five Indonesians, and one Myanmar national in the crew.

"We have found the vessel and RMAF (Malaysian air force), MMEA (Malaysian coast guard) and RAAF (Australian air force) aircraft are tailing it from the air," Aziz said, according to Channel News Asia.

Related: Fuel-Siphoning Attack on Thai Tanker Highlights Spike in Piracy Around Asia

MT Orkim Harmony: Latest photo with the new name 'KIM HARMON' — Abdul Aziz Jaafar (@ChiefofNavy)June 18, 2015

Malaysia has reportedly sent eight ships and four planes to the South China Sea as the negotiation team communicates with the hijackers.

"We are in negotiations with them," the director for the Malaysian coast guard, Vice-Admiral Ahmad Puzi, told Channel News Asia. "The distance between us and them is not very far. We are keeping visual distance and are watching their movements. We need to study various aspects before deciding the next course of action."

Authorities believe the pirates are operating under a syndicate working to steal fuel from ships. The MT Orkim Harmony is the second oil tanker captured by pirates in June, with the vessel carrying $5.7 million in fuel with 2 million gallons of gasoline.

Malaysia has reported five thefts at sea off its southern coast so far this year. Attacks on small tankers are on the rise in the waters off Southeast Asia, according to the International Maritime Bureau, with notably high number of hijackings around Bintan Island in Indonesia. Last year, 11 ships were captured in the South China Sea.

The Associated Press contributed to this report.