Le Thi Dieu Linh was reported missing from her tour group in the York City in the northeastern county of North Yorkshire on Tuesday afternoon, said the Vietnamese Embassy in London.

Tour guide Nguyen Ba Thanh Tung from Ho Chi Minh City-based travel company Travel Plus came to the embassy to report the case two days after it happened, the embassy said.

Tung was the one touring the city with Linh prior to the incident. He had also reported to the police in York.

After questioning Tung, North Yorkshire police had decided that he was free to go and the tour guide returned to Vietnam on Saturday.

North Yorkshire police said Linh was last seen with an Asian man aged about 20 on Coney Street near a bus station in the afternoon when she vanished.

Linh was wearing a white jacket, light blue denim shorts and carrying a white rucksack while the man dressed in a dark top and a black baseball-style cap.

Linh speaks no English, police said, adding that they are "increasingly concerned" for her safety and believe she "could be anywhere in the country," the BBC reported.

So far, police have detained eight people they believed to have connection with her disappearance.

Vietnam’s Ministry of Foreign Affairs has instructed the embassy in London to keep related agencies there in touch and get itself ready to implement necessary citizen protection measures.

Her family in Vietnam has been informed.

The U.K. is a major destination for Vietnamese human trafficking victims.

At least 3,187 Vietnamese victims have been identified since 2009 until recently, according to official data.

About 362 possible child victims from Vietnam were discovered in England in 2017, up more than a third over 2016.

Victims trafficked from Vietnam most commonly end up being exploited, often in cannabis farms and nail bars, but many are also sexually exploited, according to a report commissioned by Britain’s Independent Anti-Slavery Commissioner Kevin Hyland.