Students at medical schools around the United States staged "die-ins" to protest the chokehold death by police of an unarmed black man, and New York activists demanded the city take action after a grand jury declined to indict the officer involved.
Protests intensified last week after the grand jury decision not to charge a white New York City police officer in the July death of Eric Garner. The decision came roughly a week after a Missouri grand jury did not indict a white officer in the shooting death of unarmed black teen Michael Brown.
In New York, a group calling itself the NY Justice League asked local officials to fire Officer Daniel Pantaleo over Garner's death. They also urged the state to name a special prosecutor to investigate the Garner case and called for clearer laws regarding police use of lethal force.
The group later held a news conference to announce it had the support of hip-hop impresario Russell Simmons and recording artists including Common and Immortal Technique.
Simmons, who is behind the music label Def Jam Records, said he had spoken with New York Governor Andrew Cuomo and New York City Mayor Bill de Blasio about the group's demands.
"Their demands are so legitimate and so easy to understand," Simmons said. "The fact is that we're not going away."
Students at about 70 medical schools around the country including in Chicago, Atlanta and Boston staged die-ins on Wednesday to protest the killings.
The killings of Garner and Brown have aggravated already strained relations between police and black Americans and rekindled a national debate over race relations.
At National Basketball Association games, some players including Los Angeles Laker Kobe Bryant and Cleveland Cavalier LeBron James have worn T-shirts during warm-ups that read, "I can't breathe," Garner's last words.
Even though a grand jury has decided against charging Pantaleo, he still faces the possibility of discipline from an internal police investigation into Garner's death.
Pantaleo was interviewed by the New York Police Department's internal affairs bureau on Monday for two hours, according to local radio station 1010 WINS.
On Tuesday night in Berkeley, California, which has a history of social activism, hundreds of protesters faced police in riot gear, and stone throwing was met by teargas.