The incident occurred just after 9pm local time (2am GMT) in the 3600 block of Penn Avenue, in Lawrenceville, Pennsylvania. Witnesses have claimed they saw people fleeing the scene after the device was thrown. Police have also claimed surveillance footage showed the incendiary object being thrown out of a white pickup truck.
A parked vehicle was damaged in the first incident, but no injuries or casualties have been reported by police.
Another explosion was reported just after 10:30pm (3:30am GMT) in the 200 block of Dinwiddie Street in the Hill District.
Police scanner traffic overheard by Breaking911 indicated shooting was also heard in the area.
Homeowners called officers after they said they could feel their houses shaking from the explosion.
Police officers have said they are still investigating the second incident, and are reviewing CCTV footage.
They said they do not believe anyone was being targeted by the attacks, and added it is too early to say if the two incidents were connected.
Pittsburgh Bureau of Police posted the information on their Facebook page, as well as appealing for information on the incidents.
Pittsburgh’s police headquarters can be called at (412) 323-7800.
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