The husband of an Australian teacher who was shot dead in Kenya last week has been arrested in connection with her death, in addition to another man.

Gabrielle Maina's estranged husband, Cyrus Bernard Maina Njuguna, and another man, John Njuguna Waithira, were arrested on Tuesday.

The lawyer representing the men, Wilfred Nderishu, told the ABC the men were innocent and was seeking their release from custody.

Loading

He said there was evidence to show the men were not at the scene or involved in the shooting.

Ms Maina was shot dead while walking home last Thursday. The killing shocked the small community of Karen, where she lived.

A post mortem was conducted on Ms Maina's body on Monday.

It found she died from a single gunshot wound to the neck. The bullet travelled down her body and exited through her back.

The autopsy was carried out by Kenya's Chief Pathologist Dr Johansen Oduor.

Ms Maina moved to Kenya in 2015, and was the head teacher at Hillcrest Preparatory School in Karen. She had previously worked as a teacher in New South Wales and attended university at the University of New England in Armidale.

Ms Maina was an active member of the tight-knit community in the Nairobi suburb of Karen. Last Saturday, members of the local Karen Vineyard Church said prayers and expressed shock and sorry over her death.

Investigations are continuing.