NEW YORK (CBSNewYork) -- The search is on for the man who police say was seen on surveillance video violently robbing and sexually assaulting a German tourist in Harlem.
It happened just before 3 a.m. Thursday on West 146th Street.
The graphic video shows the 31-year-old woman struggling with a man for her purse as he repeatedly punches her, police said. When she falls to the ground, police said he sexually assaulted her before running off with her bag.
NYPD Chief of Detectives Robert Boyce said the punches knocked out the victim's teeth, 1010 WINS' Al Jones reported. She was taken to the nearby hospital in stable condition.
The first person to see the video was building manager Corry Sheeley when he arrived at work the next morning.
"I was pretty shocked when I saw it," he told CBS2's Magdalena Doris. "I said, 'How can anybody do that and sleep at night?' Apparently he's got some issues."
Sheeley handed that incriminating video over to police, aiding the investigation.
"It pretty much happened right where we're standing," he said. "I just scrub up the blood and what was left."
The encounter came to a violent conclusion near a stack of trash. It was loud enough that people could hear it in their apartment as they slept, but it didn't register as an attack.
No one realized the woman needed help.
"I heard something like, somebody throwing away some garbage. That's what I heard," Mirala Jimenez said.
Investigators had been looking into whether the attack was connected to a similar incident that happened on Monday, April 24 near 154th Street and St. Nicholas Avenue. By Friday, a suspect had been taken into custody, and was being questioned in that case.
In that case, police said a 35-year-old Manhattan woman was approached from behind as a man simulated a gun being pointed to her.
The suspect stole her purse and repeatedly punched her in the head before ripping at her pants and forcibly groping the victim, police said.
"Right now, they look to be the same cases, the same MO without the sexual assault in the first one," Boyce said.
In both incidents, Boyce said the attacker announced "I have a gun -- give me your bag."
"At which point, he grabs the bag from her and doing so, pushes her to the ground and punches her several times," Boyce said.
Boyce said police tracked a credit card stolen in the first robbery and know the man's identity.
As CBS2's Lou Young reported, violent street crimes are uncommon in the neighborhood -- historic Hamilton Heights; even overnight the area is considered safe.
The attacks, in close proximity, have neighbors on edge.
"As a woman, you should be able to walk your neighborhood and feel safe," resident Nicole Wilkins said. "I'm really sorry those women had to go through that."
"I was shocked," another woman told 1010 WINS' Roger Stern. "I was like, 'on my gosh, how could something like that happen around here?'"
Police are researching recent robbery suspects in the area, looking at nearby homeless shelters and scouring the neighborhood for more surveillance video, Doris reported.
"We are asking everybody in this neighborhood, that if they know this individual to call the police immediately. In Manhattan North my chief there ha sput on extra patrols to see if we can get this person picked up today," Boyce said.
Anyone with information about either case is asked to call the NYPD's Crime Stoppers Hotline at 1-800-577-TIPS (8477) or for Spanish, 1-888-57-PISTA (74782), visit www.nypdcrimestoppers.com or text tips to 274637 (CRIMES) then enter TIP577.
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