Serena Williams has spoken of her concern for her members of her family after the deaths of two black men by police last week. The killings of Philando Castile and Alton Sterling sparked global condemnation prompting widespread protests.

At a Black Lives Matter rally in Dallas on 7 July, five police officers were killed and seven others injured when a lone gunman opened fire in a targeted attack against law enforcement officers.

Speaking at a news conference after her historic Wimbledon win, the tennis champion said that the current tensions in the US in the wake of the killings are 'painful'.

"I do have nephews and I'm thinking 'do I have to call them and tell them don't go outside? If you get in your car it might be the last time I see you'. That's something that is of great concern, because it would be devastating. They're very good kids.

"I don't think the answer is to continue to shoot our young black men in the United States, or black people in general," she said.

"Violence is not the answer in solving it." Commenting on the deaths of five police officers in Dallas, she told Sky News: "The shooting in Dallas was very sad. No one deserves to lose their life. The entire situation is extremely sad and is something that is very painful to see happening."

Watching Serena Williams on centre court was close friend Beyonce, who had earlier penned an open letter decrying the deaths. Celebrities have been uniting calling for an end to the violence.

The five police officers shot and killed by a sniper during a protest in Dallas have been named as: Senior Corporal Lorne Ahrens, Michael Krol, Sergeant Michael Smith, Police Officer Patrick Zamarripa, and Police Officer Brent Thompson, of the Dallas Area Rapid Transit Police Department.

DART said that three officers — Omar Cannon, 44, Misty McBride, 32, and Jesus Retana, 39 — were also shot during the protest, but are expected to recover from their injuries.

Dallas sniper shootings: The five police officers who lost their lives IBTimes UK

The bloodshed marked the deadliest day for law enforcement in the United States since the September 11 terrorist attacks of 2001.

The shooter, identified as Micah Johnson, was killed after a 12 hour stand-off with police, using a bomb detonated with a robot, after he was heard shouting that he "wanted to kill white people, especially white officers."

The White House has claimed that Johnson was a lone attacker with no terrorist links, who it is believed was acting out of revenge for the killings of two black men - Alton Sterling and Philando Castile - by police this week.