April 18 (UPI) -- South Korea's conservative opposition said Thursday a total of six ships that have accessed South Korean ports have been smuggling North Korean coal and violating sanctions.
Yoo Ki-june, a lawmaker with the Liberty Korea party, said he has evidence that DN5505, a Togo-flagged ship, was found violating sanctions, South Korean news service News 1 reported.
Yoo, the chairman of a special parliamentary committee that's investigating North Korean sanctions violations, said an independent probe found the ship was smuggling North Korean coal, according to the report.
There are now a total of six vessels of concern to South Korean authorities that have been identified for sanctions-violating actions, ranging from fuel transfers at sea to coal smuggling.
The DN5505 was taken into custody in early February after it entered a South Korean port. The vessel had departed from Nakhodka, a port city in the Russian Far East, and was carrying 3,217 tons of fuel and coal.
The ship also docked at South Korea's Pohang New Port in November to unload 2,588 tons of fuel and coal, Yoo said.
"The cases of suspected violations of sanctions against North Korea are being revealed, and if the cases are not clarified, it is impossible to know how rampantly violations or suspected violations are taking place," Yoo said Thursday.
Conservatives have criticized President Moon Jae-in for not undertaking more thorough investigations of sanctions violators.
The heaviest sanctions against North Korea began to be enforced in 2016 in response to multiple weapons provocations, including suspected hydrogen bomb tests.
Sanctions could be hurting North Korea's elite class, The New York Times reported Thursday.
North Korea has asked the United States to lift the last five rounds of sanctions, according to the report.
The two countries ended their most recent summit without a deal in Vietnam.