Kenya's government has ordered an investigation after more than 12,000 false names were found on its payroll.
The fictitious names were discovered after authorities started biometrically registering all civil servants in September.
Kenya's anti-corruption commission and anti-bank fraud unit have been asked by the cabinet to start investigations.
Kenya is ranked 136 out of 177 nations by Transparency International on its perception of corruption index.
An audit earlier this year found that at least $1m (£600,000) a month was lost in payments to "ghost workers", as well as other financial irregularities.
The government suspects that former staff were continuing to receive salaries after leaving the civil service.
"[The] cabinet directed immediate investigations following revelations... there were in excess of 12,000 staff who were unaccounted for," a statement said, after a ministerial meeting led by President Uhuru Kenyatta on Thursday.
Detectives from Kenya's Directorate of Criminal Investigations have also been tasked with investigating officials over the revelations.
More than 12,500 names of government employees who failed to show up for the biometric registration were struck off the payroll at the start of November, Kenya's Daily Nation quotes Anne Waiguru, minister for devolution and planning, as saying.
President Uhuru Kenyatta vowed to fight corruption in the public service after taking office in April last year.