New York -- Police released the name of a woman who was found dead in a suitcase and were still searching for a suspect seen on a surveillance video rolling the suitcase on a New York block.

Police identified her as Betty Williams, 28, from the Bronx. Williams was strangled and then stuffed into the dark-colored suitcase, authorities said. The suitcase was found Wednesday night.

A grainy video, released by police, shows a man dressed in a dark knit hat and leather jacket with light-colored pants, pulling the dark-colored 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.

Later, the woman's body was found in the suitcase, and blood was leaking from the luggage, 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."

"We're talking to relatives, and we hope to have more definitive information about her acquaintances that will help in the investigation," Kelly said.

The New York Police Department is seeking the public's assistance in identifying the suspect in the video, according to a police statement.