The deaths of of two black men, Alton Sterling and Philando Castile, at the hands of US police sparked protests this week. They are just two in more than 100 African-Americans who have been killed in 2016 in situations where excessive police force has been alleged.

Out of the 560 people killed by US cops in 2016, 136 of those were African-American, according to the Guardian. That constitutes 24 percent of the victims – yet blacks make up just 12.6 percent of the overall US population.

Institutional racism remains a major problem in areas such as employment and housing, according to activists from the Black Lives Matter movement while police brutality against people of color has become all too regular.

Not ONE conviction for police murders of innocent black people. No accountability. Police reform NOW. @potuspic.twitter.com/E8qXr4yara — Rashida Jones (@iamrashidajones) July 7, 2016

A recent survey by the Pew Research Center showed that a large proportion of black Americans (84 percent) believe they are treated unfairly by law enforcement compared to white citizens. Just 50 percent of whites agree, with 58 percent of the overall population of the opinion that the police treat blacks worse than whites.

Here are six instances of African-Americans who died at the hands of US law enforcement or while in custody that sparked protests and discontent across America.

Michael Brown

On August 9, 2014, Darren Wilson shot and killed 18-year-old Michael Brown bringing the town of Ferguson into the spotlight. The teenager was seen shoplifting and then leaving a convenience store on CCTV footage, while a police issued a call for a suspect.

@hautedamn Meet Michael Brown, 18. Killed by Ferguson police officer Darren Wilson. pic.twitter.com/e0cUkqmLEd — ️ (@beyances) July 6, 2016

Brown was spotted and questioned in the back of the police car and following a scuffle between Wilson and Brown, the teen attempted to grab a gun from the officer who then shot him on the hand. Brown attempted to flee the scene and was shot dead.

Freddie Gray

Gray was arrested in Baltimore on 12 April 2016, accused of carrying an illegal switchblade – an allegation one of the arresting officers made. Prosecutor Marilyn Mosby said later it had been a legal knife, therefore the arrest was not justified.

The fourth police officer facing charges in the death of Freddie Gray opts for a bench trial. pic.twitter.com/t5DXmRUIvR — AJ+ (@ajplus) July 5, 2016

Gray had repeatedly requested his inhaler after being handcuffed and police put him into a tactical hold before he was put in the back of a van. Once he was “on his stomach head first into the wagon,” according to Mosby, he was not restrained with a seat belt and despite repeatedly requesting medical attention, his pleas were denied. He fell into a coma and died later in hospital with 80 percent of injuries to his spine.

Eric Garner

Footage filmed by onlookers showed 43-year-old father Eric Garner being tackled to the ground by police in New York City and could be heard repeatedly gasping, “I can’t breathe,” while officers put him in a chokehold. Once Garner lost consciousness, police turned him onto his side to help him breathe, but it was too late. He died in hospital an hour later.

BLACK MALE EXECUTED BY BATON ROUGE POLICE



Police murdered Eric Garner for cigarettes. Now Alton Sterling over CD's. pic.twitter.com/j2sCMTdbRu — Liz Howard (@mdvitm) July 7, 2016

Tamir Rice

The shooting of 12-year-old Rice sparked outrage across the US after the boy was killed by two officers in Cleveland in November 2014. A 911 caller had reported a possible juvenile pointing “a pistol” towards random people and despite the caller stipulating twice that the gun was “probably fake”, police arrived at the scene and shot the boy dead.

tamir rice // died at the age of 12, we love you pic.twitter.com/GIjjuZAjvP — greg (@n9viv) July 6, 2016

His gun had been a toy, according to Rice’s mother, who was also reportedly threatened with arrest once arriving on the scene. Rice’s 14-year-old sister was also forced on the ground and handcuffed after running towards her brother, around two minutes after the shooting. Footage of the incident showed that police waited four minutes before providing any first aid to the victim.

Walter Scott

On April 4, 2015, Walter Scott was shot by white police officer Michael Slager in North Charleston, South Carolina. Scott was stopped for a non-functioning third brake light on his car and after some questioning from his vehicle, he exited his car and ran away with Slager chasing him.

RIP Walter Scott - unarmed; shot and killed by North Charleston PD. pic.twitter.com/qNabgCURWa — Jay Taj (@jaytaj) July 7, 2016

In footage captured by an eyewitness, 50-year-old Scott was seen running away from the officer and then shot in the back. The witness who filmed the incident initially said he almost deleted the video out of fear for his life.

Sandra Bland

The case of Sandra Bland remains disputed between the account of police officers and activists. Though Bland died under the supervision of police, authorities maintained they had no part to play in her death.

The 28-year-old black woman was found hanged in her jail cell in Texas last year. Authorities classed her death as a suicide but activists have continued to maintain racial violence was the cause.

RIP Sandra Bland - unarmed; killed by Waller County officers under dubious and unsolved reasoning while in custody. pic.twitter.com/7Jkd6PQy4K — Jay Taj (@jaytaj) July 7, 2016

Bland was stopped by officer Brian Encinia on July 10, 2015, for failing to signal while changing lane. In what was captured by the policeman’s dashcam, interaction between both parties became heated and Bland refused to get out of her car.

She was then forcibly removed from the vehicle after being threatened with a taser and subsequently arrested. Bland was overheard in the footage stating that the officer slammed her head to the ground. On July 13, she was found dead in her cell.

Protesters accused the police of racial profiling and called the cause of death homicide, not suicide.