Police are hunting for a man who fatally stabbed his girlfriend with a kitchen knife and them slit her throat in Nairobi's Huruma area.
He escaped after the killing on Wednesday night. The motive was not established.
Residents only knew the woman as Maggy and didn't know the man. The couple moved there two weeks ago. Efforts to identify both are underway.
In Obama estate, Kayole, a woman was arrested after fatally stabbing her husband in another domestic quarrel on Wednesday night. The motive was not established.
Police had to shoot in the air to disperse a mob that wanted to lynch the woman.
Nairobi police boss James Mugera said the bodies were moved to the mortuary ahead of identification and autopsy.
He said both assailants would be charged with murder.
Cases of domestic violence have been on the rise in city estates, many of them fatal.
Calls are increasing for couples to solve their differences amicably but few people appear to listen.
"The victims had more than two stab wounds, showing a motive was to kill was there, even if one was provoked," Mugera said.
Meanwhile, police and prison officials are looking for a robbery-with-violence juvenile who escaped on Wednesday night from Kamiti Maximum Security Prison.
The boy scaled a wall, jumped into the staff compound and later walked away.
Officials searched near Kamiti and Kahawa West without success.
(Edited by V. Graham)
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