A moment's silence for slain police officers was interrupted by chants of 'Black Lives Matter' during the Democratic convention.

Dallas Sheriff Lupe Valdez was on stage paying a stirring tribute to the five officers who were gunned down in her city on July 7.

The veteran officer then asked the crowd to remember all of the cops who had fallen in the line of duty with a quiet moment of reflection.

She said: 'Please help me to honor ALL of America's fallen officers with a moment of silence.'

Then members of the crowd shouted the controversial slogan, and it was heard all around Philadelphia's Wells Fargo Center.

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Dallas Sheriff Lupe Valdez arrives on stage to address delegates on the fourth and final day of the Democratic National Convention at Wells Fargo Center in Philadelphia

A moment's silence for slain police officers called for by Dallas Sheriff Lupe Valdez was interrupted by chants of 'Black Lives Matter' during the Democratic convention

Valdez ignored the jeers and carried on with her speech.

'I am privileged to introduce to you some of the brave family members left behind by our fallen officers. Let's hear from them,' she said.

Jennifer Louden, Wayne Walker and parents Wayne Owens and Barbara Owens then walked out onto the stage.

They all had loved ones who were killed while working as police officers.

Wayne Owens, Barbara Owens and Jennifer Louden, family members of fallen law enforcement officers stand on the stage during the final day of the Democratic National Convention in Philadelphia

Family members of fallen law enforcement officers stand onstage on the final night of the Democratic National Convention in Philadelphia

Jennifer Loudon addresses the Democratic National Convention in Philadelphia

Protesters walk through the halls of the Wells Fargo Center with a banner reading: 'Don't vote for Hillary. She killin [sic] blk [sik] people'

During her rousing speech, Valdez told the crowd that she was the youngest of eight children brought into a family of migrant workers.

'When I told my father that I was going to join the police, he got angry. You see, he and my older brothers had been beaten by the police for no legitimate reason.

'But I stuck with my decision. Years later, whenever I visited, he'd show my badge off to his friends. He saw the good I was doing in my job, and he was proud of me.

'And I am proud of my fellow officers. When my officers report for duty, they have no idea what might come up that day. When they respond to a domestic violence call, they don't know whether a relieved victim or an abuser with a gun will answer the door.

'When they stop a vehicle, they have no idea whether the driver is racing to the hospital to deliver a baby or fleeing the scene of crime.

'They don't know whether the next 911 call will be their last. But they keep showing up. They keep answering the call.

Valdez was on stage paying a stirring tribute to the five officers who were gunned down in her city on July 7. The veteran officer then asked the crowd to remember all of the cops who had fallen in the line of duty with a quiet moment of reflection

Then members of the crowd shouted the controversial slogan, and it was heard all around Philadelphia's Wells Fargo Center

'They keep putting their lives on the line. They are doing the best they can to protect our communities. We put on our badges every day to serve and protect, not to hate and discriminate.

'We lost five officers in Dallas on July 7. They were gunned down as they were protecting citizens protesting the police.

'It has been a tough time for Dallas, Baton Rouge, and other law enforcement communities all across America who have lost officers to violence. I've been trying to make sense of it.

'Violence is not the answer. Yelling and calling each other names is not going to do it. Talking within our own group in a language only our group understands leads nowhere. We have to start listening to each other.

'My deputies have worked hard to reach out to the communities we serve. We attend all sorts of events: Ramadan, Cinco de Mayo, Juneteenth, Pride, veterans' parades – you name it.

'We show up, and some of our officers are uncomfortable at first. But, the only way to serve your community is to know your community.

'Last Sunday, after working in the morning, I went in uniform to meet my partner for lunch at a nice restaurant.

'As I handed the server my credit card, he smiled and said that at least four tables had already offered to pay for our meal.

'My girlfriend and I both teared up. There wasn't a single person in that restaurant I knew. The people of Dallas knew that even though our men and women in uniform were hurting, we never stop doing our job.'