The 50-year-old suspect was arrested in the U.S. state of Georgia and his fingerprints matched those found on a homemade silencer used in the killing, New York Police Commissioner Raymond Kelly said Tuesday.
Dr. Daniel Malakov, 34, died Oct. 28 while taking his 5-year-old daughter to see his ex-wife. The couple had been embroiled in a bitter custody dispute.
As the child went to greet her mother, a gunman approached and fired three rounds into Malakov's chest.
On Nov. 5, Malakov's ex-wife testified in Queens Family Court that he had abused her; a divorce lawyer who represented the shooting victim said it was not true.
Investigators had found records of the suspect's fingerprints from a 1994 arrest for farebeating, Kelly said.
The death shocked his close-knit community of Bukharan Jews from the former Soviet republic of Uzbekistan.
Malakov emigrated to the United States from Tashkent, one of tens of thousands of Bukharan Jews who arrived in the 1990s after the dissolution of the Soviet Union. He studied at New York University and Columbia University.