The Cheonghae Unit, which includes South Korean special forces, arrived in the strait on Tuesday aboard the 5,000-ton destroyer Choi Yong, according to the South Korean Defense Ministry.
Established in 2009 as South Korea’s first overseas anti-piracy force, the Cheonghae Unit had been deployed to the Gulf of Aden, between Somalia and Yemen, to help maintain the free movement of South Korean vessels through the region.
Almost a year ago, the unit’s area of operations was expanded to include the Gulf of Oman and the Persian Gulf, about 1,800 kilometers (1,118 miles) to the east, as tensions spiked in the region.
That expansion came after officials in the United States, a key South Korean ally, asked for help in safeguarding international shipping in the region, although Seoul stopped short of joining a US coalition to protect the route.
Tensions in Persian Gulf have increased in the past week, near the one-year anniversary of the deadly US strike on Qasem Soleimani, a top Iranian general.
Then on Monday, Iranian boats seized the South Korean-flagged chemical tanker Hankuk Chemi as it transited the Strait of Hormuz, the narrow entrance to the Persian Gulf from the Arabian Sea.
Five South Korean nationals are among the 20 civilian mariners aboard the tanker, the South Korean Foreign Ministry said.
Choi Young-sam, a spokesman for South Korea’s Foreign Ministry, said Tuesday the government in Seoul is in close communication with counterparts in Tehran and is trying to secure the release of the sailors and the vessel.
There was no suggestion the Cheonghae Unit would be undertaking a rescue operation, with the Defense Ministry saying it would be advising other South Korean-flagged vessels in the area on safety.
Yet the unit has pulled off rescues of South Korean nationals in the region before — most notably in 2011, off the coast of Somalia. In that action, commandos from the Cheonghae Unit stormed a South Korean tanker that had been hijacked along with its crew of 21 by a gang of Somali pirates.
The commandos killed eight pirates and captured five others, according to the South Korean Defense Ministry. None of the tanker’s crew died.
The Cheonghae Unit also freed South Korean nationals captured by pirates on a Singapore-flagged merchant ship in 2012 and supported the evacuation of South Korean nationals from Yemen in 2015, the government said.