The four sailors are now being checked by doctors aboard a South Korean naval vessel.
SEOUL - Four South Korean sailors abducted by Somali pirates 19 months ago were released on Saturday, South Korea's Foreign Ministry said.
The MT Gemini, a tanker operated by Singapore-based Glory Ship Management, was hijacked by the pirates on April 30, 2011, with the four sailors, along with 21 non-Korean crew members, while heading to Malaysia from Kenya.
The pirates freed the vessel seven months later along with the non-Korean sailors, but kept the four Koreans captive, breaching an earlier agreement to release all crew members.
"All four (South Korean) sailors have been freed on Saturday," a ministry statement said.
It added the sailors, now on a South Korean navy destroyer, would return to Seoul by air once health checks and other procedures were completed.
South Korea's Yonhap news agency and other media quoted Seoul officials as saying the sailors appeared to be in good health and that the government backed the Singapore company in negotiations with the pirates. There was no information on whether a ransom had been paid.
South Korea has deployed a navy destroyer with about 300 troops in the Gulf of Aden since early 2009 to comply with a U.S.-led multinational campaign to quell frequent piracy by the Somalis, a legacy of the country's two-decade civil war.