(CNN) -- Twenty people were killed in violence south of Baghdad and in Mosul on Wednesday, including 10 members of the same family, police officials said.
Gunmen in Latifiya, south of the capital, stormed the home of a Shiite family at dawn, and opened fire, killing two mothers, two fathers and their children, the officials said.
One day earlier, gunmen stormed the house of a Sunni Muslim family in southern Baghdad, killing five family members in their sleep, according to police.
This comes as Sunni-Shiite frictions have escalated since an April incident in Hawija, in northern Iraq. That's where Iraqi security forces raided a site used by Sunni protesters to demonstrate against the Shiite-led government.
Sunnis have felt politically marginalized under Shiite President Nuri al-Maliki, whose government fears that Sunni Islamists, who've been involved in fighting in neighboring Syria, are now targeting it.
Separately, police reported three attacks in Mosul on Wednesday.
The deadliest involved a suicide bomber who blew himself up at a police station, killing five officers, the officials said.
Two people were shot while driving in western Mosul. Three others were reported killed when mortar rounds landed in the central part of the city.
More than 800 Iraqis were killed and another 2,030 wounded in violence and acts of terrorism last month, the United Nations said.
August's toll was lower than July's. But, said the agency's assistance mission for Iraq, "the impact of violence on civilians remains disturbingly high."
July was the deadliest month in Iraq since the peak of sectarian violence in 2006 and 2007. According to U.N. figures, 1,057 Iraqis were killed and another 2,326 were wounded in July.