Zaki, who had surrendered in a UP court on November 20 in another case, was arrested yesterday, police said.
The accused, along with his friend Javed, allegedly shot at Binno and her mother Sadmani in Nizamuddin in south Delhi on November 19, they said.
The incident occurred when Sadmani noticed that their neighbours Javed and Zaki were urinating in front of their house and raised objection, leading to a heated argument, police said.
The accused left while threatening the victims, police said, adding, the duo returned when the mother and daughter were having dinner and opened fire.
During investigations, it came to light that both the accused had past criminal records.
Javed had come out of jail in April 2012, while Zaki had a criminal case of attempt to murder registered against him in Gulawathi in UP.
"Police team found out that Zaki had surrendered before court in Gulawathi on the very next day of the murder from where he had been sent to Bulandshahar Jail. He was formally arrested yesterday and has been brought on police remand," police said.