The police said that they were investigating what led to the shooting, saying they did not know whether it was related to a botched robbery, a dispute or anything tied to their religion or race. “There’s nothing in the preliminary investigation that would indicate that they were targeted by their faith,” said Henry Sautner, a deputy inspector in the New York Police Department.

A law enforcement official, speaking on the condition of anonymity because of the active investigation, said that the crime did not fit any existing pattern and cautioned that the motive was still wide open. “What it does seem is that it was planned, to some extent,” the official said. “It looks more like a targeted shooting than anything else.”

Detectives have not found video footage of the shooting itself, nor have they located an eyewitness, the official said.

Image Alauddin Akonjee

That video shows the gunman following the two victims. “There is no question that he was targeting them,” the official said. “But it’s hard to say why.”

One snippet of video shows the victims walking, with the suspected gunman following deliberately behind, the official said. Then, they go out of the frame of the camera. Around 15 seconds later, another video shows the same man “running back,” alone, after the shooting, the official said.

“Unfortunately, because we don’t have yet good video coverage of the actual shooting, it’s hard to say what transpired,” the official said. “Witnesses said they heard several shots. They saw the guy running with the gun in his hand.” No one has said they heard the gunman speak during the shooting.