US intelligence whistleblower Edward Snowden sought shelter among Hong Kong refugees after he leaked a huge trove of secret documents in the southern Chinese city, reports said Wednesday.

The former intelligence contractor had quit his job with the National Security Agency and travelled to Hong Kong in May 2013 where he initiated one of the largest data leaks in US history, fuelling a firestorm over the issue of mass surveillance.

Although Snowden stayed in an upscale hotel before the leak, little was known of his situation afterwards.

But a report Wednesday revealed he had been given shelter by the city's 11,000 asylum-seekers.

Many of Hong Kong's refugees are forced to live in slum-like conditions, the last place anyone would look for one of the highest-profile US fugitives.

The 33-year-old stayed with at least four refugees, according to a New York Times report. It added they were all clients of lawyer Robert Tibbo, who helped hide Snowden.

"It was clear that if Mr. Snowden was placed with a refugee family, this was the last place the government and the majority of Hong Kong society would expect him to be," Tibbo told the Times.

One Filipino woman with whom Snowden stayed, Vanessa Mae Bondalian Rodel, described him as "scared and very worried".

After she saw his story in local media, she described her shock. "Oh my God, the most wanted man in the world is in my house."

Other refugees from Sri Lanka said they were not worried about hosting Snowden, and felt he was taking a greater risk than they were.

One family told how he left money for them under a pillow before he left.

Snowden came to Hong Kong on May 20, 2013 and began a damaging series of leaks about the NSA eavesdropping of phones and computer systems that triggered concern from governments worldwide.

Media were clambering to find the whistleblower from the time he checked out of his five-star hotel on June 10 to the day he left the city for Moscow on June 23, escaping the clutches of US justice.

His high-stakes journey is the topic of "Snowden", a thriller directed by Oliver Stone which hits cinemas around the world in September and comes to Hong Kong in October.