(Corrects Jan. 8 story in paragraph 3 to show Kibaki not seeking another term)
* Security forces under spotlight ahead of vote
* Man accused of impersonating top policeman, robbery
* Arrest exposes "serious systemic weaknesses" in police
By Humphrey Malalo
NAIROBI, Jan 8 (Reuters) - Kenya pledged on Tuesday to root out impostors in its police force following the arrest last week of a man suspected of masquerading for a decade as a top provincial security official.
Joshua Waiganjo, who said he was an assistant commissioner in the Rift Valley region, appeared in court on Tuesday to face 10 charges of serious crimes including impersonating a police officer and highway robbery, prosecutors said.
The case has caused a public outcry in the east African nation, where persistent corruption scandals have undermined confidence in the government ahead of a presidential election on March 4.
An internal police investigation found that Waiganjo had leaked information that caused the massacre of 32 police officers in November when they were pursuing cattle raiders, Kenyan newspaper The Standard reported.
Johnston Kavuludi, head of the independent National Police Service Commission, said it would seek to establish if Waiganjo had access to confidential security information and whether there was any link between him and the massacre in Baragoi, 210 miles (340 km) north of the capital Nairobi.
"The incident has exposed serious systemic weaknesses in the police service," said Kavuludi. "The commission is undertaking a detailed audit of all the police officers in the service, an action that would weed out 'ghost' officers."
Waiganjo's lawyer, Katwa Kigen, told Reuters his client "has nothing to do with the Baragoi massacre".
He said Waiganjo was not an impostor and they would prove his innocence of all the charges.
UNIFORMS FOR SALE?
Media showed photos of a middle-aged Waiganjo wearing the uniform of senior officers and flying in a police helicopter. They carried tales of junior policemen he had intimidated and even sacked from the force over the years.
He attended several planning meetings for the doomed mission to recover stolen cattle, The Standard reported, quoting the report of the internal investigation.
Kavuludi said the police commission had suspended John M'mbijiwe, the Rift Valley police boss, and two other senior officers in the region to facilitate its probe.
The commission said a committee leading the investigation would report back within three weeks.
In 2006, two Armenian brothers - Artur Margariyan and Arthur Sargsian - whose swaggering lifestyle turned them into celebrities - were found to have been fraudulently issued with certificates showing they held the rank of deputy commissioner.
They were accused of involvement in a police raid on media offices and were deported after assaulting customs officers.
President Kibaki appointed a new police chief last month to bolster the force ahead of the March presidential vote.
It will be the first since a disputed 2007 election provoked ethnic clashes that killed more than 1,200 people and threw a spotlight on the failings of Kenya's security forces. (Additional reporting by Anthony Gitonga in Naivasha; Writing by Duncan Miriri; Editing by George Obulutsa and Tom Pfeiffer)