A medic based at the Kisii Training and Referral Hospital and his lover were found dead at an apartment in Nyamataro area, Kisii County.
The man identified as Vincent Mongare is suspected to have killed the woman first before he died by suicide in the house.
The woman was identified as only Moraa, 29.
Moraa was in Kisii for a short holiday as she stays in the US with her family, friends and relatives said.
She is believed to have another family in the US.
The apartment the bodies were found in had been locked from inside.
The bodies were discovered Friday November 29 and that of the woman was decomposing an indication she had died earlier on.
Police said that of the man was a bit fresh. Used syringes were found next to the bed in the house an indication they may have died out of injection of lethal poison.
Police said they are yet to determine when the woman died. The team that visited the scene however said the woman may have died earlier.
The man and woman were holding each other when the bodies were found on bed, police said.
The motive of the incident is yet to be established.
Detectives said they have asked pathologists to come and take over the scene and help in establishing how they died.
Their friends said the woman was unhappy after she realized a project she had been financing in Kenya was not there.
She had been sending money to the man.
The bodies are lying at the local mortuary pending autopsy.
Murder and suicide are some of the leading causes of death in the country.
Police say the suicide trend has been worrying and increasing as up to two cases are reported daily.
There are about eight murder cases reported daily.
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