By Al Novack

PHILADELPHIA (CBS) – Violence on the streets of Philadelphia kept authorities very busy early Thursday morning. There were four separate shootings within a two hour period.

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Police say they have no suspects in an early morning shooting in the 2600 hundred block of Jasper Street that claimed the life of a 50-year-old man. He was shot in the head around 2am and pronounced dead at the scene. The gunman fled and remains at large.

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Investigators are seeking three suspects in connection with an early morning robbery and shooting in the 4800 block of Whitaker Avenue.  Shots rang out at around 2:30am. Police arriving on the scene found a 53-year-old man shot twice. He was rushed to Temple University Hospital where he was listed in stable condition.

A 31-year-old man was shot in the head just after 2am in North Philadelphia. Police say the incident took place in the 2200 block of North Cleveland Street in what appears to have been a robbery.  The victim was listed in critical condition at Temple University Hospital.  Police say the gunman fled the scene and remains on the loose.

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Police are investigating the shooting of a 21-year-old man in the 3200 block of Shellbourne Street in Kensington around 1am.  The victim was shot in the back in what investigators believe may have been a drug deal gone sour. The victim is listed in stable condition at Temple University Hospital. So far, no one is in custody.