“The shooting happened when she was kneeling and someone was standing,” Ms Maina’s lawyer, George King’ori, told the ABC.

It’s believed the mother-of-two had just dropped off her son at a friend’s home.

She said the angle of the bullet wound and marks on Ms Maina’s skin suggested the former Australian teacher may have been forced to kneel on the road before she was shot.

“There were markings on her knees, showing she was most likely kneeling,” the lawyer said.

Security company Insight Secure, which monitors local incidents, said a caucasian woman was killed by “unidentified assailants” and “a 9mm cartridge was recovered at the crime scene”.

The Kenya high commission in Canberra said investigations were underway in Nairobi.

“My heart is broken especially for your Mum, brother and your gorgeous little boys who now have to grow up without their Mumma,” Ms Maina’s cousin, Annabel Smith, wrote on Facebook. 

“I wish I could just see you one last time and tell you how amazing you are, what a wonderful Mum you are.”

EARLIER:

Friends of Australian teacher Gabrielle Maina, who was killed in Nairobi, say she was “very intelligent, musically talented and always smiling”.

The former Armidale High School and University of New England (UNE) student was gunned down about 10am on Thursday, local time, while walking on Miotoni Road in the upmarket suburb of Karen.

UNE lecturer and friend, Anna Cavallaro told Fairfax Media the death of Ms Maina is a “tragic loss to humanity”.

“I’m not exaggerating because she was one of those people that you can’t forget,” she said.

“I just can’t believe it, I still can’t believe it … she was almost like a daughter (to me).”

Ms Cavallaro taught Ms Maina Italian for three years during her undergraduate degree.

“It’s very rare you get close to students,” she said.

“I think more than anything her perseverance, her determination and her positive attitude stood out.

“She liked people and having people around her, she really was a lovely person.”

Ms Cavallaro said Ms Maina was “a very good student” who met her husband while studying at UNE.

“She was living at college, I remember, at Wright Village,” she said.

“Her maiden name was Phillips and then she got married, her husband was Kenyan.

“I think he was studying here and she met him through her church group.

“She was always very religious.”

Secretary of NSW Department of Education, Mark Scott took to Twitter to express his condolences.

“Widely known, loved and respected in NSW education. A tragedy,”  he wrote.

Ms Maina graduated from UNE with a Bachelor of Arts in 2004 and a Graduate Diploma in Education in 2006.

A UNE spokesperson said the university is deeply saddened to hear of the death of Ms Maina.

“Our thoughts are with Ms Maina’s family and friends at this terrible time, we offer our condolences and support,” the spokesperson said.

Prime Minister Malcolm Turnbull said the death of the teacher was a “tragic event”.

“And our prayers and love and condolences go out to her family and loved ones,” Mr Turnbull told Melbourne radio station 3AW.

Ms Maina taught in a number of NSW public schools and spent almost five years as an English and Drama teacher at Sarah Redfern High School in Sydney.

School friends say she “was very intelligent, musically talented and always smiling”. 

The 40-year-old was shot and killed in a robbery while walking home in the Kenyan capital at about 10am on Thursday, local time.

Fairfax Media understands Ms Maina graduated from Armidale High School in 1995 before commencing studies at the University of New England.