NEW YORK (AFP) ― U.S. reporter Glenn Greenwald returned to his homeland Friday for the first time since he helped expose Washington’s vast electronic spying network, warning that more revelations are yet to come.

Greenwald, who maintains regular contact with fugitive former NSA contractor Edward Snowden, flew into New York with filmmaker Laura Poitras to receive a journalism award for their coverage.

Greenwald and Poitras had feared they could be detained upon arrival but told reporters at a Manhattan hotel that, while U.S. officials “deliberately created” a sense of risk, they faced no problem.

Based in Brazil with his partner, who was arrested at London’s Heathrow airport and briefly held last August, Greenwald said he wants to travel freely to the United States without fear of harassment.

He paid tribute to Snowden, saying the young technician had taken an enormous risk in orchestrating the largest intelligence leak in U.S. history, which has triggered a global debate about mass surveillance.

Greenwald maintains regular contact with the man he and many supporters consider a whistleblower, but who has been branded a traitor and a security threat by several U.S. officials.

“I don’t think we could help the U.S. government get to him in Russia,” Greenwald said when asked about his contact.

He also warned that the vast trove of documents given to him and Poitras and other journalists by Snowden before he fled to Russia still contain many startling secrets that have yet to emerge.

“In my opinion the stories that are the most significant and most shocking and will have the broadest and most enduring implications are the ones we’re currently working on,” he said.

Poitras, an award-winning American filmmaker based in Berlin, said she had been stopped nearly 40 times over the last six years at U.S. borders but had no problem on Friday.

She said there was a “very real” risk of being subpoenaed.

“The fact that we’re here is not an indication that there isn’t a threat. We know there is a threat,” she told reporters. “The reason we’re here is we’re not going to succumb to those threats.”

Greenwald and Poitras shared the George Polk Award for national security reporting with Ewen MacAskill of The Guardian and Barton Gellman of The Washington Post, who also covered Snowden’s leaks.

Greenwald, MacAskill and Poitras interviewed Snowden last June in Hong Kong, where he first revealed himself after fleeing the United States with his vast stockpile of secret NSA documents.

James Clapper, the U.S. director of national intelligence, has branded the journalists Snowden’s “accomplices,” telling them to return stolen documents to prevent “more damage” to U.S. security.

Greenwald, who broke the story for The Guardian, now heads the editorial board at The Intercept, a new online magazine backed by eBay founder Pierre Omidyar.

The awards were established in 1949 by Long Island University to commemorate Polk, a U.S. correspondent murdered in 1948 while covering the Greek civil war.