New York (CNN) -- New York police said Friday they have new video showing what they called a "person of interest" in the case of a woman whose body was found in a suitcase earlier this week.
Detectives from New York's 23rd precinct, in the city's Harlem neighborhood, made the video public two days after the victim's body was found. Police had earlier released a separate, grainy video showing what they believe is the same man, rolling a suitcase down a street.
The new video shows a dark-skinned man, wearing a black winter hat and a heavy jacket, at a store. He appears to be carrying several items when he enters the store, takes money from his wallet, and eventually leaves after making some purchases.
Police did not detail how they got the new footage, where it came from, or at what time it was shot.
On Thursday, police identified the victim as Betty Williams, 28, from the Bronx. Williams was strangled and then stuffed into the dark-colored piece of luggage, authorities said.
Blood was leaking from suitcase when it was found Wednesday night, police said.
"The cause of death is strangulation," Police Commissioner Ray Kelly said Thursday. "We initially announced it was trauma to the back of the head -- that was the belief of the investigators at the scene."
Shortly after the find, the first video was released showing a man dressed in a dark knit hat and leather jacket with light-colored pants, pulling the suitcase near a stoop in East Harlem.
The man pauses as three people walk by before hauling the suitcase past a dark-colored sport utility vehicle and out of the camera's sight.
The New York Police Department is seeking the public's help in identifying the suspect in the videos, according to a police statement. Those with information are encouraged to submit tips online at www.nypdcrimestoppers.com or call 800-577-TIPS.
"We're talking to relatives and we hope to have more definitive information about her acquaintances that will help in the investigation," Kelly said.
CNN's Julia Talanova contributed to this report