He says this included approaching another member of the Sri Lankan community on the streets of Hong Kong, where they asked for some of the families by name, and carried "photographs and files" about them.

Forced to move

Supun Kellapatha said that after hearing the reports, he felt he wasn't safe to walk in the streets.

Ajith Puspakumara, another Sri Lankan asylum seeker who helped Snowden, said he is also "very scared," adding that "this situation is not safe for me here."

Tibbo says that when he learned about the situation in late December, he immediately moved the families to "safe locations."

Relatives in Sri Lanka of one of the families had been "questioned, harassed and threatened" by Sri Lankan officials, Tibbo said.

Tibbo called on Hong Kong authorities to protect the families, because he thinks they're at risk of being "unlawfully renditioned" out of Hong Kong.

"We do not believe that the Hong Kong government has provided the protection that our clients are entitled to receive as asylum seekers in Hong Kong," Tibbo says.

Tibbo says he has already reported the issue to the Hong Kong Immigration Department, and says he will ask the Hong Kong Police to investigate the matter and "prevent any illegal cross-border law enforcement activities."

In a statement sent to CNN, Hong Kong's Police Public Relations Branch said that if a person feels threatened, they should seek help from the police.

"The Basic Law only authorizes law enforcement agencies of Hong Kong to enforce laws in Hong Kong."

"If there is any illegal act, the Police will handle in accordance with the law," it added.

CNN has also reached out to the Sri Lankan government's Ministry of Foreign Affairs for a comment, but they have not yet provided a response.

Hong Kong lawmaker James To, a member of the Democratic Party, is supporting the asylum seeker's case, and says he will raise the issue with authorities.

"We must protect Hong Kong's system against any abuse by foreign governments," To said. "So we will take the matter to the Hong Kong government, to the highest level."

'We are part of history'

Edward Snowden is "aware" of the situation and has "grave concerns" for the families, Tibbo says.

The families went public after their brush with history was immortalized in the Oliver Stone film "Snowden."

"They protected me, they believed in me, and but for that I may have had a very different ending," Snowden later told the New York Times.

"We are part of history because we did good things," Supun Kellapatha told CNN in October last year.