Federal investigators says Billy Street threatened to blow up his ex-wife's family's home with children inside.
Billy Street's ex-wife's mother did not want to be identified but she says Street is a terrifying and disturbed individual.
"My family has been living in a nightmare," she said. "He is a master manipulator and he is a sociopath."
Street was arrested after police say he threatened his ex-wife's family last week.
According to a criminal complaint, Street threatened to blow up the home of his ex-wife's mother with her four grandchildren inside, including his own 10-year-old daughter.
The victim tells us, he sent her a photo of what appears to be a homemade bomb and then texted her a disturbing message.
'"I'm going to put a bomb under your pillow, (bleep). I'm going to kill your mother, your grandmother, your daughter, I'm going to kill your whole family,'" she said. "When he says something, he will do it. I don't put anything past him."
Street's own mother told 7 Action News Reporter Anu Prakash Wednesday that her son is bipolar and has threatened people before, including her.
The man's ex-mother-in-law said, "He gets out of jail and the vicious cycles starts all over again."
She tells us he has had a long history of violence.
"He has shot through my mother's home before. He has kidnapped my daughter at gunpoint before when she was five months pregnant with his child. He's climbed through the window of my mother's home in the middle of the night."
Street divorced his wife eight years ago.
The victim says her daughter moved to South Carolina last month to get away from Street.
"The way people are in the world today, if someone says that they are going to kill you, you better take it serious."
Police take it seriously, too.
Authorities learned Street had a flight on November 3 to South Carolina.
He was arrested at the airport.
Street's family said they found what appeared to be a homemade device hidden in the crawl space of their home, leading the victim to believe he is capable of murder.
"If they let him out, I'm terrified."
Street is in federal custody.