Four Family Bank employees have been arrested in connection with theft of Sh20.8 million at the lender’s Ruiru branch on Saturday night.
The thieves emptied the bank’s strong room and ATM machine.
The suspects will be held for the next seven days to allow further investigations.
They include the branch manager Charity Wanjiku, operations manager Jane Wanjiru, operations supervisor Cyrus Mugo and watchman Robert Nduriru.
Kiambu DCIO Samuel Wambugu on Tuesday applied to Senior Kiambu Principal Magistrate Stella Atambo to detain them for investigations.
According to police reports, the heist was discovered by the bank's security manager on Sunday afternoon when he visited the bank on routine checks.
The manager, John Muchiri, told the police he discovered after opening the bank that the alarm system was tampered with and the fire alarm system vandalised.
Officers from Ruiru police station established that the thieves cut through the kitchen rooftop to gain entry.
"They managed to access the strong room to the safe by cutting the door using welding gas cylinder power and further accessed the branch's ATM machine using claw bars and welding gas power," read the police statement.
The stolen cash was in Kenyan and dollar denominations.