By David Greene and Jeanmarie Evelly

A 21-year-old man was shot and killed on Saturday on Bainbridge Avenue and E. 198th Street — the third homicide this week in the 52nd Precinct.

The shooting took place outside of 2843 Bainbridge Avenue, at 4:26 a.m. on Saturday. The victim, identified by police as Edwin Valdez, 21, of the Grand Concourse, was shot once in the chest and died a short time later at St. Barnabas Hospital. One witness claimed to have heard multiple shots fired before observing a group of teens fleeing north on Bainbridge Avenue. Police canvassed local hospitals, believing the gunman was also shot, but have not identified the shooter. Police have no suspects and continue to investigate.

Valdez’s death marks the third homicide to take place within the confines of the NYPD’s 52nd Precinct in the last week, since Nov. 1, when a 35-year-old man was stabbed to death on Grand Avenue, near Devoe Park. The following day, another man, 59-year-old Bimal Chanda, died from injuries sustained during a beating just blocks away in the stairwell of his apartment building on W. 190th Street.

On the day of his attack Chanda, a longtime resident with deep ties to the community, was in the process of moving out of the neighborhood because he  was concerned about increasing crime, according his friend Mohammed Ali, who is a member of Community Board 7.  Police are still looking for two men suspected in the attack.

The string of violence this week nearly doubles the murder rate this year for the 52nd Precinct, from 4 to 7 deaths. In 2010, there had been 8  murders at this point in the year.