A conservative activist has filed a lawsuit against U.S. President Barack Obama, the U.S. Department of Justice and the U.S. National Security Agency after news reports that the NSA has been collecting the phone records of a large number of Verizon Communications customers.

A British newspaper ,the Guardian, reported Wednesday that the NSA, with authorization from the U.S. Foreign Intelligence Surveillance Court, has been collecting the phone records of a large number of Verizon customers.

On Thursday, the Guardian and the Washington Post reported that the NSA and the U.S. Federal Bureau of Investigation also have access to servers at Google, Facebook, Microsoft and other major providers of Internet services, collecting audio, video, email and other content for surveillance. Some of the companies denied that the NSA and FBI have access to their servers.

Larry Klayman, the founder of watchdog websites Judicial Watch and Freedom Watch and a former DOJ prosecutor, filed the lawsuit Friday in U.S. District Court for the District of Columbia, he said in a statement on the Freedom Watch site.

Also named as defendants in the lawsuit are U.S. Attorney General Eric Holder, NSA Director Keith Alexander, Verizon, and Roger Vinson, the judge who signed the order allowing the surveillance.

Reasons for filing the suit

“Here, there is no doubt that this massive illegal seizure had to be authorized and approved at the highest levels of the executive branch, which necessarily leads to the president, attorney general, and the director of the NSA,” Klayman said on the website. “These violations of free speech, prohibitions against unreasonable search and seizure, and due process rights are unprecedented in American history.”

The surveillance violates the First, Fourth, and Fifth Amendments to the U.S. Constitution, Klayman alleged.

The programs raise questions about the independence of the Foreign Intelligence Surveillance Court, which approved the collection of phone records, he added.

“It would appear that Obama and his government yes men know no constitutional bounds, and the courts are no longer independent such that they will protect American citizens from this tyranny,” Klayman said.

Obama's response to the news stories

Obama defended the programs during a press conference in California, saying they are a valuable tool in fighting terrorism. Congress approved the surveillance programs, and there’s constant oversight by courts, the president said. The lawmakers and judges who’ve approved the programs “cherish the Constitution,” he said.

The NSA programs reported on this week represent a “modest encroachment” on privacy rights, he said.

Obama said he welcomes a national debate about NSA eavesdropping. The U.S. needs to “strike a balance” between privacy and security, he said. “I think it’s important that the American people understand that there are some tradeoffs involved,” he said.

Obama, when running for president in 2008, criticized surveillance programs under then-President George Bush. The U.S. public shouldn’t have to choose between security and privacy, Obama said then.

Representatives of the DOJ and Verizon didn’t immediately respond to requests for comments on the lawsuit.