Mount Vernon police say they are investigating a homicide.

Officers were seen canvassing the scene on Eastchester and Mundy lanes on Saturday.

One neighbor said he heard the sounds of gunfire.

"I heard a group of small shots and then after that, I heard a very large caliber shot and then a couple of them and that's it," he said.

Another neighbor told News 12 by phone that she had witness some unusual activity from her apartment window.

"After the last four shots, a young boy ran out of the building of this complex here," she said. "Yes, he ran out after the four shots. He ran out and was watching his back."

Police told News 12 the crime investigation spanned several blocks, including Eastchester Lane, South 9 Avenue and South 11th Avenue.

Police had not detailed the sequence of events or released any information about the victim as of Saturday night.