The UN staffer who allegedly battered his ex-lover was on Wednesday arrested at Ridgeways estate, Nairobi.
Alphonse Kambu will be held at Kasarani police station until Thursday, when he will appear in court to take a plea, OCPD Wambua Mboloi said.
Lawyer Cliff Ombeta said Kambu was arrested while leaving his house, after a two-day police search.
He will answer allegations of battering 26-year-old Ruth Gakii, Ombeta told the Star on phone on Wednesday.
Speaking separately, Gakii said Kasarani police called asking her to go to the station after Kambu's arrest.
"I am about to leave the house. One thing I will not do is to negotiate with Kambu. I have nothing to tell him, I just want him to leave me alone. Let us meet in court tomorrow," she said.
Kambu, a computer programmer with UNEP, and Gakii, a business woman in Nairobi, were living together but separated 2 years ago.
It is believed the 47-year-old attacked and injured Gakii at Jacaranda estate, as their three-year-old son looked on.
Gakii was admitted to Nairobi women’s hospital.
The UN staffer has since apologised to Gakii's family saying his intention was not to hurt her, but her father declined the apology and demanded Sh40 million compensation.
DPP Keriako Tobiko asked the DCI to "thoroughly" investigate Kambu, who hails from Papua New Guinea, over the allegations.