What happened the night police killed Breonna Taylor?

The police killing of Breonna Taylor has sparked a global call to “arrest the cops” involved, galvanising a movement condemning police brutality and demanding justice in the wake of police killings of black Americans.

A Kentucky grand jury is expected to report its findings in Ms Taylor’s death on 23 September, more than six months after police fired into her Louisville apartment in March.

The city has anxiously waited for a decision whether prosecutors will charge Jonathan Mattingly, Myles Cosgrove and Brett Hankison for their role in her killing.

Ms Taylor, a 26-year-old emergency medical technician, was at home in bed with her boyfriend Kenneth Walker on 13 March when officers from Louisville Metro Police Department entered the apartment shortly after midnight.

Police believed suspects in a drug case had used her apartment’s address to receive packages, though the suspects they were investigating were miles away from her home.

A judge had signed a so-called “no-knock” warrant that gave officers permission to enter; the couple reportedly heard the sound of people banging on the front door and they called out asking who was there.

Before the raid, the warrant’s order had changed to “knock and announce,” but Mr Walker told police that the officers did not announce themselves.

Mr Walker also told police he believed Ms Taylor’s ex-boyfriend was trying to break in.

He fired a gun when police broke down the door, hitting officer Mattingly’s leg.

Police returned fire, striking Ms Taylor five times.

Mr Hankinson was fired three months after Ms Taylor’s death for "wantonly and blindly" firing 10 rounds into her apartment, according to then-interim Louisville Police Chief Robert Schroeder.

“I don’t know what’s happening,” Mr Walker said during a 911 call. “Someone kicked in the door and shot my girlfriend.”

The warrant was one of several involved with the drug-trafficking case – a suspect was arrested more than 10 miles from Ms Taylor’s apartment the same night she was killed.

The Jefferson County coroner has said that she died within a minute after she was shot.

None of the officers wore body-mounted cameras that night, and none of them have been charged with any crimes.

Police disputed Mr Walker’s account, and the officers’ incident report contained several errors, including listing Ms Taylor’s injuries as “none” and claiming they did not force entry, despite breaking the apartment door using a ram.

Charges filed against Mr Walker for firing his weapon were dropped.

The other two officers were placed on administrative reassignment.

Kentucky’s attorney general Daniel Cameron is leading the investigation.

Earlier this month, Louisville settled a lawsuit filed by Tamika Palmer, Ms Taylor’s mother, awarding her estate $12m and committing the city’s police department to reform and transparency measures.

The city banned the use of no-knock warrants in June, and officers are now required to wear body cameras while executing search warrants.