Guerino Annarumma left the 114th precinct in handcuffs, sources say, to help police find the gun that was used to shoot his estranged wife and to kill her daughter.
He is the lone suspect, and police and neighbors say he has a history of violence and threats against his wife.
"We saw him drive, I ignored him," a neighbor said.
But the courts did not.
"This as the order of protection I have," said Helene Sherman, Olga Annarumma's divorce attorney.
There were two orders of protection issued against Guerino Annarumma regarding his wife.
"She wanted nothing, she would just say 'he's crazy,'" Sherman said.
A neighbor threw a piece of cardboard over the bloodstains left after 57-year-old Olga Borodina Annarumma, Guerino's estranged wife, and her daughter 25-year-old Valeria Kuzmina Lowery were shot at their home Monday morning.
Neighbors say Guerino Annarumma had a violent and contentious relationship with the two.
Guerino didn't hide his contempt or his intentions.
In several blogs, he ranted about the two: "God will make you pay," he wrote in one.
And in another, "Remember one thing. Whatever goes around comes around. One day it will come to you and your mother, I don't have nothing to lose," he wrote, "You are going to pay for whatever you did. I don't play no games," he wrote cryptically, "Good luck. Bye bye."