Philadelphia police shooting of Black man sparks unrest

A Philadelphia police officer is covered with an unidentified red substance during a confrontation with protesters, Tuesday, Oct. 27, 2020, in Philadelphia. Hundreds of demonstrators marched in West Philadelphia over the death of Walter Wallace Jr., a Black man who was killed by police in Philadelphia on Monday. (AP)

Protesters confront police during a march, Tuesday Oct. 27, 2020, in Philadelphia. Hundreds of demonstrators marched in West Philadelphia over the death of Walter Wallace, a Black man who was killed by police in Philadelphia on Monday. Police shot and killed the 27-year-old on a Philadelphia street after yelling at him to drop his knife. (AP Photo/Matt Slocum)

A man is detained by police in Philadelphia, Tuesday, Oct. 27, 2020. Hundreds of demonstrators marched in West Philadelphia over the death of Walter Wallace Jr., a Black man who was killed by police in Philadelphia on Monday. Police shot and killed the 27-year-old on a city street after yelling at him to drop his knife.  (AP Photo/Matt Slocum))

A demonstrator raises a fist near Philadelphia police in Philadelphia, late Tuesday, Oct. 27, 2020. Hundreds of demonstrators marched in West Philadelphia over the death of Walter Wallace Jr., a Black man who was killed by police in Philadelphia on Monday. Police shot and killed the 27-year-old on a Philadelphia street after yelling at him to drop his knife. (AP Photo/Matt Slocum)

Debris is thrown at Philadelphia police during a demonstration in Philadelphia, Tuesday, Oct. 27, 2020. Hundreds of demonstrators marched in West Philadelphia over the death of Walter Wallace Jr., a Black man who was killed by police in Philadelphia on Monday. Police shot and killed the 27-year-old on a Philadelphia street after yelling at him to drop his knife.  (AP Photo/Matt Slocum)

Philadelphia police officers form a line during a demonstration in Philadelphia, late Tuesday, Oct. 27, 2020. Hundreds of demonstrators marched in West Philadelphia over the death of Walter Wallace Jr., a Black man who was killed by police in Philadelphia on Monday. (AP Photo/Michael Perez))

A protester points while facing police during a demonstration Tuesday night, Oct. 27, 2020, in Philadelphia. Hundreds of demonstrators marched in West Philadelphia over the death of Walter Wallace Jr., a Black man who was killed by police in Philadelphia on Monday.  (AP Photo/Michael Perez)

Protesters face off with police during a demonstration Tuesday, Oct. 27, 2020, in Philadelphia. Hundreds of demonstrators marched in West Philadelphia over the death of Walter Wallace Jr., a Black man who was killed by police in Philadelphia on Monday. (AP Photo/Michael Perez)

Protesters, including two carrying part of a barricade, walk during a demonstration Tuesday night, Oct. 27, 2020, in Philadelphia. Hundreds of demonstrators marched in West Philadelphia over the death of Walter Wallace Jr., a Black man who was killed by police in Philadelphia on Monday.  (AP Photo/Michael Perez)

A trash bag is thrown at police during a demonstration Tuesday night, Oct. 27, 2020, in Philadelphia. Hundreds of demonstrators marched in West Philadelphia over the death of Walter Wallace Jr., a Black man who was killed by police in Philadelphia on Monday.  (AP Photo/Michael Perez)

Debris is thrown at police during a demonstration Tuesday night, Oct. 27, 2020, in Philadelphia. Hundreds of demonstrators marched in West Philadelphia over the death of Walter Wallace Jr., a Black man who was killed by police in Philadelphia on Monday.  (AP Photo/Michael Perez)

Protesters march during a demonstration Tuesday, Oct. 27, 2020, in Philadelphia. Hundreds of demonstrators marched in West Philadelphia over the death of Walter Wallace Jr., a Black man who was killed by police in Philadelphia on Monday.  (AP Photo/Michael Perez)

A demonstrator confronts a police officer outside the 18th District Police station during a rally after the death of Walter Wallace Jr., a Black man who was shot and killed by police in Philadelphia, Pennsylvania, October 27, 2020. (REUTERS/Bastiaan Slabbers)

Demonstrators raise their fists in front of police officers during a rally after the death of Walter Wallace Jr., a Black man who was shot by police in Philadelphia, Pennsylvania, October 27, 2020. (REUTERS/Bastiaan Slabbers)