While Congress is on recess and President Obama vacations in Martha's Vineyard, a coalition of free press groups is escalating an already-aggressive campaign against the Obama administration for allegedly freezing out the press and cracking down on reporters.

The flood of critical letters and petitions and statements from First Amendment groups marks a new level of tension in a relationship that for years has been deteriorating. Though Obama, as a candidate in 2008, was widely seen to enjoy favorable media treatment, his administration now is fielding accusations that it's one of the least transparent in history.

Society of Professional Journalists President David Cuillier, in a statement earlier this week, blasted the administration for what he called "excessive message management and preventing journalists from getting information on behalf of citizens."

SPJ is among the groups that's been leading the charge on the issue. Last month, more than three dozen groups, including SPJ, wrote to the White House about what they described as growing censorship throughout federal agencies.

Cuillier's latest statement came in response to White House Press Secretary Josh Earnest's Aug. 11 letter to his organization regarding their complaints.

In it, Earnest said Obama's commitment to transparency is "unwavering." While he acknowledged "there will always be a healthy, natural tension between journalists and the White House," Earnest vowed greater transparency going forward and pointed to several steps the administration has taken: like processing more "freedom of information" requests, declassifying records and releasing information on White House visitors.

"Typical spin and response through non-response," Cuillier shot back.

He said he hopes the administration is "sincere" about being more open, "but we want action. We are tired of words and evasion."

Media groups are gearing up for another confrontation on Thursday, when they plan to present a petition with 100,000 signatures -- backed by the Committee to Protect Journalists, the Freedom of the Press Foundation and others -- to the Justice Department. It calls for the administration to halt legal action against New York Times reporter James Risen, who detailed a botched CIA effort during the Clinton administration to thwart Iran's nuclear ambitions.

Risen's reporting is at the center of criminal charges against former CIA officer Jeffrey Sterling. Federal prosecutors want to force Risen to testify about his sources at Sterling's trial, and the Supreme Court recently refused to get involved in the case.

Risen argued he has a right to protect his sources' identity, either under the Constitution or rules governing criminal trials. A federal appeals court in Richmond, Va., earlier rejected Risen's bid to avoid being forced to testify.

At the same time federal prosecutors have fought Risen in court, Attorney General Eric Holder has suggested that the government would not seek to put Risen in jail should he refuse to testify as ordered.

But journalist groups want assurances. Risen also is expected to speak during a press conference at the National Press Club on Thursday afternoon.

The case follows tension last year surrounding the Justice Department's snooping on Fox News' reporter James Rosen's phone records and emails, and its seizure of AP phone records in the course of leak investigations. The controversy over those actions led to some reforms at the Justice Department.

Press groups' complaints about the administration are manifold. They say agencies are prohibiting staffers from talking to journalists without public affairs office approval -- and sometimes without public affairs employees sitting in on interviews. Further, they complain about long delays in getting information and about communications staff speaking "confidentially" even on routine matters.

In yet another complaint, journalist and scientific organizations accused the Environmental Protection Agency on Tuesday of attempting to muzzle its independent scientific advisers by directing them to funnel all outside requests for information through agency officials.

In a letter, the groups representing journalists and scientists urged the EPA to allow advisory board members to talk directly to news reporters, Congress and other outside groups without first asking for permission from EPA officials. An April memo from the EPA's chief of staff said that "unsolicited contacts" need to be "appropriately managed" and that committee members should refrain from directly responding to requests about committees' efforts to advise the agency.

The scientific advisory board's office had asked the EPA to clarify the communications policy for board members, who are government employees.

"The new policy only reinforces any perception that the agency prioritizes message control over the ability of scientists who advise the agency to share their expertise with the public," the groups wrote.

The chair of that panel, H. Christopher Frey, said in an interview with the Associated Press Tuesday in which he stressed he was offering his personal opinion, that he found the tone of the EPA memo to be unnecessary.

Frey, a distinguished professor in North Carolina State University's engineering department, said that many of the scientists that seek to serve on the committees are national and internationally-renowned experts and that EPA "need not be too strong in precluding interactions with the media or others."

An EPA spokeswoman said there are no constraints on members fielding requests in a personal or professional capacity. She said the memo was designed to assure transparency.

The Associated Press contributed to this report.