The shooting, which happened shortly after 4pm in Lancaster, killed 27-year-old Ricardo Munoz, the Lancaster County District Attorney's Office said, whose office will lead an investigation into the incident.
A video filmed by the officer’s body camera showed Munoz emerging from the inside of the house and rushing towards the officer when he arrived at the residence as part of the call.
Munoz could be seen waving a knife above his head 'in clear view' and 'in a threatening manner' when the officer fired at him. It is considered as a dangerous threat to the officer’s life. The officer then reacted to the immediate threat and shot Munoz a few times before he fell to the floor.
Policemen might be safe from a far distance when the perpetrator is holding a knife, but if the attacker is close, he poses an immediate threat to them and so actions must be taken to neutralize the situation.
Although, it is too early to know whether the shooting was absolutely necessary or not, the case is being investigated.
Munoz died at the scene and no one else was hit by gunfire.
'A police-involved shooting has a significant impact on a community, as we are seeing with the large number of individuals gathering in the streets,' District Attorney Heather Adams said. 'However, I am asking that all reactions be tempered as the investigation is ongoing.'
Police were on the scene and attempted to keep order among close protesters The crowds also rallied the city's police station to continue their protests and could be heard screaming 'this is what democracy looks like.'
It was reported the windows of police vehicles were shattered amid protest against the shooting later on Sunday night.
Police Chief Jarrad Berkihiser held a brief news conference on Sunday but shared very little information about the shooting. He said that people could stay near the crime scene, but pressed them to stay calm and peaceful.
A 'final determination on the use of force' will be made by District Attorney Adams.
'We ask that acts of protest remain peaceful as violence and destruction of property will become headlines and serve no purpose for the safety and wellbeing of our citizens and neighborhoods,' the DA's office requested.
Lancaster Mayor Danene Sorace also released a statement,'This has been a heartbreaking day for our city. I grieve for the loss of life and know that there are more questions to be answered as the investigation continues.'