The emotional moment Alton Sterling's son breaks down after his dad's death.

At first, 15-year-old Cameron Sterling stood strong and composed as his mother stepped up to speak about the devastating fatal shooting of her son, Alton Sterling.

As mother Quinyetta McMillon began to speak, Cameron’s body became physically unable to contain the despair.

His unfiltered emotion flowed in front of press, the public and viewers around the US.

Alton Sterling, 37, (pictured) was fatally shot by a police officer while he was pinned to the ground outside a convenience store in Baton Rouge, Louisiana.

The event was captured by numerous bystanders, with videos uploaded to social media.

"He [her son Cameron Sterling] had to watch this, as this was put all over the outlets," Quinyetta McMillon said.

"As a mother, I have now been forced to raise a son who is going to remember what happened to his father."

Within two days, Philando Castile was fatally shot by a police officer during a traffic stop. His girlfriend live-streamed the aftermath, showing Castile covered in blood as the officer pointed his gun at him.

He was shot as he reached for his driving licence, she said.

According to The Guardian, this year alone, police in America have killed 566 people. 135 black people.

Four years ago, on February 26th, an unarmed teenager named Trayvon Martin was shot and killed by a man named George Zimmerman. Zimmerman claimed he was acting in self-defence.

In July 2013 a Florida jury acquitted him of all charges. Alicia Garza, Patrisse Cullors and Opal Tometi voiced their outrage over the verdict by posting #BlackLivesMatter on social media and the Black Lives Matter movement was born.

In August 2014, when Michael Brown was killed by Ferguson, Missouri police officer Darren Wilson, the Black Lives Matter movement really started to take hold. Millions tweeted the hashtag as violent protests erupted in Ferguson.

Like these famous voices, and as an American living in the US, I feel these deaths in the pit of my stomach.

I feel for the grieving mothers and family members.

I shudder at the thought of someone facing this kind of violence when they're simply out for a drive, coming home from work, or doing what they need to do put food on the table.

I ache at the thought that there are a huge amount of people fin my community and in communities all around the United States whose lives are seen as unimportant until a camera catches their abuse.

For all of these reason #BlackLivesMatter.