Police arrested 23-year-old Khalid Mehdiyev after he was spotted outside Ms Alinejad’s home in Flatbush, New York, last Thursday.
The NYPD said in a statement that officers found a loaded AK-47, an illegally modified magazine and other weapons when they pulled him over for running a stop sign shortly after he left her address.
Ms Alinejad, a prominent women’s rights activist and critic of the Iranian regime, told The Story with Martha MacCallum on Fox News that she wouldn’t be intimidated into silence.
“I was just in my home, working, being alone, and this man was trying to enter my home,” she told Fox News, adding that her stepchildren had been home at the time.
“When I learned from the FBI that he had a gun, loaded, ready to kill me I was shocked.”
Ms Alinejad posted security camera footage to social media showing the alleged suspect appearing to try to gain entry to her home.
“Just imagine if he had opened the door who knows how many of my neighbours would have been killed in Brooklyn, in New York,” she told Fox News.
In 2021, the FBI identified Ms Alinejad as the alleged target of a kidnapping plot by four suspected Iranian intelligence officers.
Prosecutors have charged the four men in Manhattan with plotting to lure Ms Alinejad from New York City to Iran.
Ms Alinejad became a US citizen in 2019 after being exiled from Iran over her outspoken criticism of women’s rights in the Republic.
“I don’t have any weapon. My weapon is my camera. My weapon is my voice,” she told Fox News.
Ms Alinejad has long campaigned to end the compulsory wearing of hijabs in Iran, and says women continue to send her videos of their protests: “That scares the regime. The whole regime is scared of women.”
She called on the US to do more to stand up for human rights and punish Iran’s alleged terror tactics.
“They bury human rights under a nuclear deal,” she said.
Mr Mehdiyev is facing 10 counts including criminal possession of a machine gun and unlawful possession of a large capacity ammunition feeding device. He has been locked up without bail.