The FBI today confirmed it is helping Capitol Police to investigate possible Twitter threats made against Sen. Ted Cruz.
An FBI official told ABC News authorities have already interviewed the person who posted the initial tweets and are now keeping an eye out for anyone else who might try to take action based on the information posted Friday.
The official did not say whether authorities believe there is a credible threat to Cruz, the Texas Republican who has been widely blamed for triggering the crisis that led to the government shutdown.
Federal officials often investigate such online posts out of an abundance of caution -- they often turn out to pose no credible threat.
The tweets in question were written by Troy Gilmore Jr., who identified himself as an Army and Navy veteran who served during the Vietnam era.
"Take down Ted Cruz, at his home" and "What goes around comes around CRUZ!!" Gilmore tweeted under the handle @ArmyVet54. The New Jersey grandfather also listed Cruz's purported Houston home address several times and used expletive language to criticize the Republicans and Tea Party more widely.
Cruz has been criticized by Democrats and some Republicans for spearheading a strategy of tying government funding in an effort to defund or delay President Obama's health care law.
The government shutdown ended on Wednesday night, but on the same day the Twitter threats were posted, Cruz indicated in an interview with ABC News' Jonathan Karl that he would not rule out forcing another government shutdown in his effort to "stop the train wreck that is Obamacare."
Gilmore's Linkedin page reveals he was a former prison chef and says that his objective is to get a degree in "Homeland Security and Security Global Management."
"I am trying to obtain now to make this world and my country a better and safe secure place for everyone especially my family and grand children who will still have to live in this world long after I and my generation are gone," he wrote.
ABC News' Mike Levine, Jack Date, Pierre Thomas and Jack Cloherty contributed to this report.