The robbers who stole Sh11 million from four ATMs belonging to Barclays in Nairobi over the Easter weekend belonged to one gang suspected to have worked in cahoots with employees from the bank and a security company.
On Monday, detectives from the Directorate of Criminal Investigations (DCI), who have taken over the case, detained five employees from the bank and G4S security group.
The five were arrested at Kenya Cinema on Mama Ngina Street where the fourth robbery is said to have taken place.
Among the issues the detectives want to understand is how the four ATMs were broken into without the security guards, who are normally located within the premises, noticing.
The robberies were all reported more than 24 hours after they happened, raising questions on the possible involvement of the security guards.
Another issue the detectives want to understand is how the ATMs were all robbed hours after being reloaded with money.
Additionally, Barclays is under pressure to explain why two of the ATMs did not have CCTV cameras.
Nairobi police boss Reuben Ndolo said he did not know about the fourth ATM raid, further raising questions about the nature of the robbery.
"I only know of three ATMs. No one has told us about the Kenya Cinema one," he told the Nation.
"Anyway, the investigation has been taken over by the DCI, so I can't comment on other issues about the robbery," he said.