North Korea slammed reports about the group defection of 13 of its restaurant workers in China and said that Seoul “lured and abducted” them in “broad daylight,” KCNA Watch, which carries statements from North Korean news agency KCNA, reported Thursday. The 12 restaurant workers and one manager defected to Seoul last week, marking the first mass defection of North Koreans to South Korea since 2011.

The North Koreans were reportedly from upper middle-class families and were working at a restaurant in the Chinese eastern port city of Ningbo. North Korea is believed to be operating 130 restaurants in foreign countries that generate about $10 million in cash for the Kim Jong Un regime, which has been facing sanctions from the United Nations Security Council over its nuclear advancements. KCNA cited a statement released Tuesday from a spokesman for the Central Committee of the Red Cross Society, which said that the defection had been “cooked up” by Seoul and referred to it as "provocation."

“We sternly denounce the group abduction of the citizens of the DPRK [Democratic People's Republic of Korea] as a hideous crime against its dignity and social system and the life and security of its citizens,” the statement said, according to KCNA. “The recent case of ‘group defection’ cooked up by the puppet group is a crucial provocation against the DPRK which can never be tolerated as it is an unbearable insult to the people of the DPRK.”

The statement also said that Seoul “lured and appeased” the North Korean citizens to South Korea and demanded the country to send them back “without delay.” Defectors reportedly face harsh punishments and in some cases execution on their return to the reclusive nation.

“In case the puppet group does not send them back, it will have to pay a high price for the serious consequences to be entailed by its action,” according to the statement.

A report by South Korea's Yonhap News Agency Tuesday said that about five to seven colleagues of the 13 North Koreans were hiding in China and waiting to defect to South Korea. The report had initially mentioned that the people were under the protection of the South Korean government, but a source told Yonhap Thursday that their whereabouts were not known.

“As far as I know, there are no remaining North Korean workers hoping for defection to the South,” a source familiar with North Korea told Yonhap. “It seems that there are no such people under the South Korean government's protection.”

Experts reportedly said that a lack of confirmation about their whereabouts could also increase the possibility that they have been repatriated to North Korea. An official from Seoul’s Unification ministry did not comment on their whereabouts, but said: “We cannot say anything about the issue as relevant questioning [by authorities on the 13 defectors] is under way,” Yonhap reported.

Earlier reports said that the number of North Korean defectors in the first quarter of the year rose 17.5 percent compared to a year before. The South Korean Unification ministry also said that by the end of March, about 29,000 people had defected to South Korea and further estimated that the total number could soon cross 30,000.