A Massachusetts teenager has been released after spending one month in jail for a Facebook post which police said constituted a terrorist threat. Reuters

A Massachusetts teenager has been set free after being jailed for one month for a Facebook comment in which he made reference to the Boston Marathon bombings, Reuters reports.

Cameron D’Ambrosio, an 18-year-old aspiring rapper from Methuen, Mass., posted lyrics on his Facebook page that read, “F--- a boston bomb wait till u see the s--- I do, I’m be famous rapping, and beat every murder charge that comes across me!”

After fellow students at D’ambrosio’s high school notified police of the lyrics, the Methuen, Mass., teen was promptly arrested on May 1 and charged with communicating a terrorist threat.

The arrest generated outrage among free speech activists, who argued that D’Ambrosio’s lyrics contained no specific threat and mounted an online campaign to raise awareness about the case and bolster the effort to have him freed, Boston magazine says.

It appears as though those efforts have paid off, as Lawrence District Court Judge Lynn Rooney ordered the release of D’Ambrosio after a grand jury refused to indict the teen, according to the county clerk’s office.

“The grand jury’s decision underscores what we have been saying all along: The prosecution doesn’t have a case here, and it’s a grave injustice that it has taken this long to get Cam returned to the safety of his home and family,” Evan Greer, of Boston's Center for Rights and Fight for the Future, said. “While today is a major victory for Cam, the chilling effect that this case has already had on free speech cannot be undone.”

If convicted, D’Ambrosio could have spent up to 20 years in prison.

Echoing the concerns of many who have been monitoring this case, Shirin Sinnar, an assistant professor of law at Stanford University Law School, said to Reuters, "Law enforcement wants to preempt acts of violence before they occur. ... The risk is that you sweep in people who had no intent to cause a crime."