Hundreds of protesters marched through the US city of Philadelphia for a second night, demanding racial justice after police fatally shot a black man.
The family of Walter Wallace Jr says he was suffering a mental health crisis when officers opened fire on him.
Police say they shot him because he would not drop a knife he was holding.
The National Guard as well as police reinforcements have been deployed. Authorities say 30 officers were hurt during Monday night clashes.
The city's police have also accused protesters of looting and ransacking businesses during the unrest.
Mr Wallace, 27, had bipolar disorder, and his wife told officers this before they shot him, a lawyer representing his family said.
Philadelphia also saw large protests earlier this year over police brutality and racism following the death of George Floyd in Minnesota.
What happened on Tuesday?
The marches began peacefully on Tuesday but became more confrontational as the evening drew on. Officers in riot gear arrived in squad cars, on bicycles and on buses, and used their bikes to shove protesters back from barricade lines.
Shops around the city closed early and set up barricades. Police and the city's office of emergency management said widespread looting was reported in several areas.
According to the Philadelphia Inquirer, protesters tried to erect makeshift barricades using bins. Police used pepper spray and batons after saying they were attacked by demonstrators.
On Monday, more than 300 people took to the streets to protest, and 91 were arrested. One officer was in hospital with a broken leg and other injuries after being struck by a pickup truck.
What has the reaction been?
Speaking at a campaign rally in Wisconsin on Tuesday, President Donald Trump attempted to tie the protesters to his democratic rival, former Vice-President Joe Biden, without providing evidence of a link.
"Last night [Monday] Philadelphia was torn up by Biden-supporting radicals," he said. "Thirty police officers, Philadelphia police officers, they were injured, some badly. Biden stands with the rioters, and I stand with the heroes of law enforcement."
In a joint statement, Mr Biden and his running mate, Kamala Harris, said: "We cannot accept that in this country a mental health crisis ends in death.
"It makes the shock and grief and violence of yesterday's shooting that much more painful, especially for a community that has already endured so much trauma," they added, while condemning Monday's looting, calling it a crime.
Philadelphia is the largest city in Pennsylvania, a state critical to next week's presidential election.
Mayor Jim Kenney, a Democrat, said the video of the shooting presented "difficult questions that must be answered", and that he was looking forward to a "speedy and transparent resolution" to the case.
Philadelphia Police Commissioner Danielle Outlaw said she had visited the scene and felt the "anger of the community". "We anticipate the chance of additional incidents of civil unrest," she said, vowing to take "additional steps to ensure order".
What do we know about the shooting?
Police said two officers responded to a report of a man with a weapon in the neighbourhood of Cobbs Creek in West Philadelphia at about 16:00 (20:00 GMT) on Monday.
Police spokeswoman Tanya Little told AP news agency that a man, later identified as Mr Wallace, was holding a knife when the officers approached, and instead of following orders to drop the weapon he "advanced towards them".
Both officers fired "several times", hitting Mr Wallace in the shoulder and chest, she said. One of the officers drove him to a hospital, where he was pronounced dead, according to Ms Little.
Footage shared on social media shows two officers pointing their guns at Mr Wallace as he walks towards them. The officers back away from him and shout at him to put the knife down. Shots are then fired and Mr Wallace is seen lying on the street.
Mr Wallace's father told the Philadelphia Inquirer that his son had mental health issues and was on medication. "Why didn't they use a Taser?" he asked.
At Tuesday's news conference, officials said the officers both fired seven shots each. The officers, who have not been named, were wearing body cameras and did not carry tasers.
Meanwhile, Mr Wallace's family lawyer said they had called for an ambulance - not police - to help deal with Walter Wallace's mental issues. Instead, two police officers arrived, lawyer Shaka Johnson was quoted as saying by the Inquirer.
Mr Wallace's pregnant wife told them her husband had bipolar disorder and was in crisis.
Who was Walter Wallace?
Mr Wallace was an aspiring rapper, and often recorded songs on issues including gun and police violence and racial injustice, according to relatives and neighbours, who described him as a "quiet, family man".
The Inquirer reported he was a father of eight who had been in and out of court throughout his adult life. He was awaiting trial for allegedly making threats, but this had been delayed repeatedly because of the coronavirus pandemic.
He pleaded guilty to robbery, assault and possessing an instrument of crime in 2017 after kicking down a woman's door and putting a gun to her head, Philadelphia's ABC affiliate WPVI reports. He was sentenced to 11-23 months behind bars, with a judge requiring mental health supervision.
In 2013, he pleaded guilty to assault and resisting arrest after punching a police officer in the face, the broadcaster reported, saying that a judge had ordered him to undergo psychiatric evaluation and treatment.
"I do know that he was on a regimen of lithium and that says to me he was under a doctor's care," the family lawyer said after the shooting, citing a medicine used in the treatment for conditions including bipolar disorder.
Data about the number of disabled people who are killed by police in the US is hard to come by. Conservative estimates suggest that about a quarter of those who die in interactions with police have a disability - whether mental, intellectual or physical. But other research indicates that the proportion may be far greater.