A former Marine involuntarily detained for psychiatric evaluation for posting strident anti-government messages on Facebook has received an outpouring of support from people who say authorities are trampling on his First Amendment rights.

Brandon J. Raub, 26, has been in custody since FBI, Secret Service agents and police in Virginia's Chesterfield County questioned him Thursday evening about what they said were ominous posts talking about a coming revolution. In one message earlier this month according to authorities, Raub wrote: "Sharpen my axe; I'm here to sever heads."

Police -- acting under a state law that allows emergency, temporary psychiatric commitments upon the recommendation of a mental health professional -- took Raub to the John Randolph Medical Center in Hopewell. He was not charged with any crime.

A Virginia-based civil liberties group, The Rutherford Institute, dispatched one of its attorneys to the hospital to represent Raub at a hearing Monday. A judge ordered Raub detained for another month, Rutherford executive director John Whitehead said.

"For government officials to not only arrest Brandon Raub for doing nothing more than exercising his First Amendment rights but to actually force him to undergo psychological evaluations and detain him against his will goes against every constitutional principle this country was founded upon," Whitehead said.

Raub's mother, Cathleen Thomas, said by telephone that the government had overstepped its bounds.

"The bottom line is his freedom of speech has been violated," she said.

Thomas said her son, who served tours as a combat engineer in Iraq and Afghanistan, is "concerned about all the wars we've experienced" and believes the U.S. government was complicit in the Sept. 11 terrorist attacks. One of his Facebook posts, she said, pictured the gaping hole in the Pentagon and asked "where's the plane?"

Whitehead said he found nothing alarming in Raub's social media commentaries. "The posts I read that supposedly were of concern were libertarian-type posts I see all the time," he said.

The big concern, Whitehead said, is whether government officials are monitoring citizens' private Facebook pages and detaining people with whom they disagree.

Dee Rybiski, an FBI spokeswoman in Richmond, said there was no Facebook snooping by her agency.

"We received quite a few complaints about what were perceived as threatening posts," she said. "Given the circumstances with the things that have gone on in the country with some of these mass shootings, it would be horrible for law enforcement not to pay attention to complaints."

Whitehead said some of the posts in question were made on a closed Facebook page that Raub had recently created so he questioned whether anyone from the public would have complained about them.

"Support Brandon Raub" Facebook pages have drawn significant interest, and other Internet sites had numerous comments from people outraged by the veteran's detention.

Raub's supporters characterized the detention as an arrest, complaining he was handcuffed and whisked away in a police cruiser without being served a warrant or read his rights. But authorities say it wasn't an arrest because Raub doesn't face criminal charges.

Col. Thierry Dupuis, the county police chief, said Raub was taken into custody upon the recommendation of mental health crisis intervention workers. He said the action was taken under the state's emergency custody statute, which allows a magistrate to order the civil detention and psychiatric evaluation of a person who is considered potentially dangerous.

He said Raub was handcuffed because he resisted officers' attempts to take him into custody.