E! News reports that Hannigan filed the order Thursday, claiming that 43-year-old John Hobbs from Nashua, N.H., has posted several threats of violence against her family on Facebook.
According to the news source, the order describes Hobbs as "mentally unstable," having recently been discharged from a mental hospital and having possessed a pistol permit since 2000.
A judge ruled that Hobbs must stay at least 100 yards away from Hannigan, Denisof and their two daughters and must also cease from posting anything about them online.
The order included online content attributed to Hobbs, including a comment posted to Facebook on Jan. 3 that read, "With that said, in 2013 I still can marry you tomorrow. I can kill you tomorrow too. Cause I simply like and love you as you live life. Aly...It doesn't end. Even after death."
On Jan. 14, Hobbs posted, "Aly, many years ago I said we were 'Soulmates' Well, the only way you are going to see that now is by talking in person."
On Jan. 15, he allegedly wrote, "Going to the casinos and a trip to Ca this year," and "So Alexis, I guess this means you better watch your wife, a little bit more than normal."
Hannigan detailed in her filing that the Facebook posts prompted her to seek police intervention, during which Hobbs "fully acknowledged his interest in Alyson Hannigan" to local police and agreed to visit a mental-health clinic.
After that, Hobbs began alluding that he would be going to California to see the actress.
According to E! News, a report from the Nashua Police Department supports Hannigan’s complaint.
A hearing set for March 6 will decide whether the restraining order will be permanent.