Black Lives Matter supporters, protesting the police killings of Alton Sterling and Philandro Castile days earlier, march along Manhattan streets in New York, July 8, 2016.
Black Lives Matter supporters, protesting the police killings of Alton Sterling and Philandro Castile days earlier, march along Manhattan streets in New York, July 8, 2016.

At a community prayer service in Dallas, Texas, worshiper Mike Young voiced the uncertainty rising in the grief-shrouded city and beyond after a Thursday-night demonstration against police brutality toward blacks ended with a sniper attack that killed five lawmen.

"How am I feeling? Perplexed, concerned like everyone else," Young said at a multiracial gathering Friday at the Concord Church. The African-American man continued, “Obviously, we’re concerned about the officers and their families, but we’re also concerned about other Americans that feel that their liberties have not been protected the way they should by police officers.”

The service was among vigils and demonstrations staged around the country Friday, with more planned over the weekend to share grief over the violence and to affirm common bonds.

The assemblies generally oppose violence and support the Black Lives Matter movement protesting excessive police force against African-American men. Thursday’s demonstration in Dallas decried the shooting deaths earlier in the week of two black men – one in Louisiana, the other in Minnesota – at the hands of white police officers.

A man and child take part in a march supporting th
A man and child take part in a march supporting the Black Lives Matter movement along the streets of Manhattan in New York, July 8, 2016. A sign affixed to a stroller asks, “Is my daddy next?”

Those deaths are the latest in a wave of fatal police shootings of black men. The African-American community has complained for decades about excessive force against black men, but in recent years, cellphone videos have made it easier to document incidents of police mistreatment.  

On Tuesday in Baton Rouge, Louisiana, cellphone footage showed police shooting 37-year-old Alton Sterling at point-blank range as he was being held down. 

On Wednesday evening in a suburb of St. Paul, Minnesota, the fiancée of Philando Castile managed to livestream on her private Facebook account just seconds after a police officer shot Castile several times after pulling them over for a missing tail light. Diamond Reynolds and her 4-year-old daughter were in the car when the officer opened fire.

Following sniper Micah Johnson’s Thursday-night attack on police – in which he killed five, wounded seven others and ultimately was killed – the Black Lives Matter group tweeted that it "advocates dignity, justice and freedom.  Not murder."

WATCH: Dallas Residents Come Together After Tragedy

Promoting ‘greater good’

In the nation's capital Friday, dozens of protesters demonstrated outside the Justice Department headquarters. Howard University student George Wyche, of Houston, Texas, said he believes there are no easy answers to the tension plaguing the country. "It's time for belief in the greater good of humanity," he said.

Police in Phoenix, Arizona, used tear gas and pepper spray on demonstrators as the crowd of about 1,000 people moved closer to a freeway. Protesters chanted "black lives matter" and "hands up, don't shoot" as they marched.

The marchers were initially accompanied by plain clothes police officers, but police attired in uniforms and riot gear eventually descended on the group.

Hundreds of demonstrators in Baton Rouge, Louisiana, where Sterling died, have hunkered down for a protest outside police headquarters. Rasha Rusk said she and other demonstrators intend to maintain the vigil until the officers seen shooting Sterling on the cellphone footage are charged with murder.

Peaceful protests

In New York, protesters came together at Manhattan's Union Square Friday to hear speeches.  The group of about 300 people later split up, with some crossing the Williamsburg Bridge into Brooklyn. Another group walked up to the Grand Central Terminal, where they chanted "black lives matter."

In Los Angeles, rappers Snoop Dogg and The Game headed a peaceful march to police headquarters, where they met with the mayor and the police chief about how to improve the relationship between police and minority communities.

In Denver, Colorado, Black Lives Matter supporters are holding a sit-in for 135 hours: an hour for each of the black people they say have been killed by police nationwide this year. The demonstration, which began Thursday, is set to continue until Tuesday. People have been dropping off food and water for the demonstrators camped out in Civic Center Park.

Protests also took place in various other American cities late Friday.