At 3.16am on Wednesday, undercover police officers in Kayole, Nairobi, received a message from a colleague on their WhatsApp group.
Four suspects who had escaped their dragnet on Manyanja Road at 11pm, were in Lower Chokaa area, on Kangundo Road, he said.
The officer had been called by a greengrocer who informed him that four people, including a woman, were robbing residents.
Some officers did not see the message and so he called members of his company, one by one.
They then called their driver to pick them up and asked for reinforcement from uniformed colleagues on night patrol.
The description of the gang was familiar -- four men and a woman, and they wore the same clothes the officers had seen a few hours earlier.
The gang was elusive and the officers had to carefully plan how to ambush it, even though they did not have sufficient information on the mode of transport the four were using.
When the police officers arrived in Chokaa, the four suspects attempted to escape.
The officers fired in the air, ordering them to surrender, but two of them who had pistols began firing back, according to the police.
The woman and a man who were shooting at the police were killed while the other two escaped on foot.
The dead woman was still clutching a Beretta pistol, which had six rounds of ammunition, police said.
Its serial number had been obliterated.
There were seven spent cartridges at the scene, police added.
WOMEN AND CRIME
Kayole OCPD Joseph Gichangi said his officers took the two bodies to City Mortuary.
"According to our sources, the woman was the wife of a well-known robbery suspect, who is at large," Mr Gichangi said, adding that the police were looking for the escapees. "We will definitely arrest them."
Mr Gichangi admitted that cases of women being recruited into criminal gangs are on the rise.
After the shooting, a mysterious social media user claiming to be a plainclothes police officer and going by the names Hessy wa Kayole, Hessy wa Dandora and Hessy wa Huruma took to Facebook, identifying the woman as Clare Mwaniki, the wife of a "notorious" robber known as Mwanii.
"Hayawi hayawi huwa. Clea Adi Vybz mnakumbuka nikimpea warning awache wizi na bwanake Mwanii???? (Clea Adi Vybz, do you remember me warning her to stop committing robberies with her husband Mwanii?)," Hessy wa Kayole posted.
In an apparent reference to a post on a Facebook page called 'Dandora Love People' in March warning the woman and others that the law would catch up with them, the Facebook user went on to recall a warning to Clare to stop carrying the gun for her husband.
"Sabrina Hassan, Mungu alikuokoa (Sabrina Hassan, God saved you)," Hessy said in the post on 'Kayole Crime Free' and 'Dandora Crime Free' Facebook pages and warned another woman to stop her criminal activities.
Hessy, who has in the recent past posted pictures of suspects, warning them of death, named Clare and Mwanii as members of the dreaded Kayole-based gang known as Gaza.
Hessy is the subject of discussion in some social media pages run by suspected gangsters.
Here, pictures of people said to be plainclothes police officers stationed in different parts of Nairobi are posted.
It is not clear if the groups are run by the same person.
The Facebook accounts Hessy wa Dandora, Hessy wa Kayole, Hessy wa Eastlando and Hessy wa Huruma also remain mysterious.
There is however speculation that they are administered by a police officer or officers in different parts of the city.
Clare's social media profiles reveal a vibrant young woman, probably in her early or mid 20s, with multiple piercings and a silver tooth.
She describes herself as a former University of Nairobi student and a lover of life.
Nairobi Police Commander Japheth Koome said many criminal gangs have female members.
Besides Gaza, gangs in the city include Superpower (Eastleigh), Brothers (City Centre), Usiku Sacco (Umoja), Msako Empire (Huruma), Jeshi la Embaa (Embakasi), Munyipi (Mathare) and Kosovo Boys (Kosovo).
"The women are used to transport guns, gather information while some even take part in robberies," Mr Koome said, adding that they also take food to male suspects in hiding.
He said the involvement of females in crime was a challenge to the security as officers are not allowed to search handbags.
"We are employing some other strategies which I will not divulge as they will jeopardise our operation," he said.