SEOUL, South Korea — A United Nations official on Tuesday called for an investigation into whether 12 North Korean waitresses were brought to South Korea against their will, saying that some had told him they had not known where they were going when they made the journey in 2016.

The 12 women and their manager left Ningbo, China, where they worked at a restaurant run by the North Korean government, in April 2016, arriving in South Korea two days later. The South’s government promptly announced their defection, which was the most sensational in years, involving a large group of people who, as workers abroad, belonged to the North Korean elite.

But the government’s account of the episode was disputed in May by the manager and four of the women. Interviewed by a South Korean news channel, those women said they had been brought to the South against their will, and the manager said he had been pressured into doing so by South Korea’s intelligence agency.

Tomás Ojea Quintana, the United Nations special rapporteur, said Tuesday at a news conference in Seoul, the South’s capital, that some of the women who defected had confirmed part of that version of events in interviews with him. “From the information that I have received from some of them, they were taken to the Republic of Korea without knowing that they were coming here,” he said, using the official name of South Korea.