Sacramento: The family of an unarmed black man shot to death by police officers in the backyard of his grandparents’ house in Sacramento, California, disputes the police account that he had earlier been breaking windows, the family’s attorney said on Friday.

Two officers, responding to a report of someone shattering car windows, fatally shot Stephon Clark, 22, on Sunday night.

The encounter was captured on video.

Police on Wednesday released body camera and helicopter video of the shooting in Sacramento, the state capital, sparking street protests the next day.

“This family completely rejects anything that the Sacramento Police Department tried to claim to justify this execution of their loved one,” said Benjamin Crump, the family’s attorney. He said the police had been untruthful, saying that police initially told the family Clark had a crow bar but the only item found by Clark’s body was a cell phone.

Crump previously represented the family of Michael Brown, the black teenager whose 2014 shooting death by police in Ferguson, Missouri, near St. Louis, sparked nationwide protests.

Since Brown’s death, a series of killings of unarmed black men by police across the United Stated has fuelled a nationwide debate about racial bias and the use of lethal force.

On Sunday night, police said, Sacramento County sheriff’s deputies in a helicopter saw Clark break a sliding-glass door at a neighbouring house, then hop a fence into a backyard.

When officers confronted Clark in the backyard, he was holding an object officers feared was a firearm and they shot him 20 times, police said. It was later discovered he only had a cell phone.

Investigators found three damaged cars in the neighbourhood, police said.

The deputies in the helicopter did not capture video of Clark breaking the glass door, Sacramento police spokeswoman Linda Matthew said. “I believe they turned on the camera after that happened,” she said by phone.

Sacramento police have not released the names of the two officers who opened fire, who have been placed on leave. Police have cited concerns about the officers’ safety, saying threats were made against them.

One of the officers is white and one is black, Matthew said.

There were more protests over the shooting in Sacramento on Friday, with dozens of demonstrators marching in the street.

The windows to at least one vehicle were broken and protesters tried to block intersections, Matthew said. One protester was arrested for allegedly breaking the window of a commuter bus, but there no immediate reports of injuries, police said.

Later Friday night, a small knot of protesters continued to block streets downtown while a group of about 200 people gathered in the South Sacramento neighbourhood where Clark’s grandparents live. A few people held candles and impromptu speeches were given in his memory.

The Sacramento County District Attorney’s Office is investigating the shooting.