Australian teacher Gabrielle Maina killed in robbery in Nairobi

 An Australian teacher has been shot and killed in a daylight street robbery while walking home in the Kenyan capital of Nairobi.

Gabrielle Maina was gunned down at about 10am on Thursday, local time, while walking on Miotoni Road in the upmarket suburb of Karen, Fairfax Media has confirmed.

Gabrielle Maina: Photo: Twitter/@HillcrestKE

Gabrielle Maina: Photo: Twitter/@HillcrestKE

Insight Secure, a security company that monitors local incidents, reported that a "caucasian woman" was killed by "unidentified assailants" and that "a 9mm cartridge was recovered at the crime scene."

Fairfax Media understands Ms Maina's purse was snatched by the rider or riders of a "boda boda" motorcycle.

Ms Maina was working as the headteacher at Nairobi's Hillcrest Preparatory School, according to the school's website.

A statement from Hillcrest said: "It is with great sadness and shock that we are writing to let you know that Gabrielle Maina, Head Teacher of Hillcrest Prep has been tragically killed whilst out walking this morning.

"She was returning home after dropping her son at a friend's house.

"Condolences to Gabrielle's family."

The teacher's biography on the school's website says Maina "relocated to Kenya in September 2015, a long term goal to establish her family here so her children can grow up with their extended family."

"After completing her postgraduate degree in Education, she was engaged by the New South Wales Department of Education, where she taught at a number of schools in the Sydney metropolitan area."

A Facebook page believed to belong to Maina says she is from Armidale, New South Wales.

A Department of Foreign Affairs and Trade spokesperson said the department was providing consular assistance to the family of an Australian woman who died in Kenya.

"Due to our privacy obligations, we will not release further details," the spokesperson said.

- with Miriam Webber