Nairobi - As Kenya heads toward a highly contested presidential election, many are worried about a repeat of deadly violence seen in past votes. The Kenyan group Mothers of Victims and Survivors is calling for all sides to maintain peace during this year's polls.

Benna Buluma, also known as Mama Victor, is clutching photos of her two deceased sons at her makeshift home in the Mathare section of Nairobi.

Election time brings painful memories to the 48-year-old widow.

On August 9, 2017, her sons; Benard and Victor Okoth, both young men, were shot dead following a police crackdown on election protests in the area, just a day after the presidential polls. Five years later, the killers still have not been held accountable.

If it was my sons who had killed someone on the road, they would have been arrested, says Buluma as she fights back tears. But the police who killed my sons have not been arrested to date, she says, and that is what pains me the most. I ask myself why, she adds. They are all human beings, and the law should serve everyone equally.

Mathare, one of the biggest slums in Africa, with some of the most densely populated poor neighborhoods in Nairobi, has remained a constant hotspot of election violence.

MarryAnn Kasina is the co-founder of Social Justice Center, an organization that advocates for social justice in Nairobi.

"Every time we have elections, they know what our issues are, but they have not actualized,' Kasina said. 'So, bringing your manifesto, to say that you are bringing water, you'll do this...it just brings horizontal violence because you are already living in poverty. It is violence already living in it, you know."

Mama Victor founded the group Mothers of Victims and Survivors Network to help families seek justice.

The group is urging election authorities and participants in the August presidential election to refrain from violence.

We want a peaceful election, she says. And that's not all - we, as mothers of victims, we want justice for our children, and compensation, she adds.

The Kenyan police have been accused of using excessive force in handling past election-related protests.

With just over a month to the general elections, the National Police Service says it is prepared to provide a secure environment for the polls to run peacefully.

In a statement to VOA, police spokesperson Bruno Shioso said steps have been taken to improve security, including new election security training and additional equipment for officers.

Past elections in Kenya have been marred by deadly violence. In the most notorious incident, more than 1,100 people were killed in riots and attacks after the disputed 2007 vote.

But, as the clock ticks toward this year's balloting, observers are cautiously optimistic that the polls will be peaceful.