Gachagua Accuses DCI of Cover-Up After New Details Emerge in Dr Victoria Mutiso Murder Probe
The investigation into the killing of prominent Kenyan mental-health researcher Dr Victoria Nthunya Mutiso has taken a dramatic political turn after former Deputy President Rigathi Gachagua accused the Directorate of Criminal Investigations (DCI) of attempting to cover up the involvement of police officers in the murder.
The accusations came shortly after the DCI released a detailed press statement on Friday, August 7, 2026, outlining the progress made in investigations into Dr Mutiso's fatal shooting in Nairobi.
The DCI statement, issued by Director of Criminal Investigations Mohamed I. Amin, gave a detailed account of the investigation, including the arrest of suspects, the alleged involvement of serving police officers, forensic findings and a possible motive linked to a longstanding land dispute.
The latest developments have now created two competing narratives: the DCI's account that investigators have made significant breakthroughs and Gachagua's allegation that the agency is shielding other individuals whom he claims were involved in the killing.
DCI Gives Detailed Account of Investigation
According to the five-page statement, Dr Mutiso was killed on the morning of July 29, 2026, while travelling in an Uber in the Upper Hill area of Nairobi.
The DCI said the Uber driver, identified in the statement as Victor Job Chunguli, had picked up Dr Mutiso from Tanga Heights Apartment on Bamboo Lane off Riara Road. She was reportedly travelling to the Africa Institute of Mental and Brain Health in Upper Hill.
The statement says the vehicle encountered a Toyota Prado that had partly blocked the road. As the driver slowed down, gunfire was heard from the rear side of the vehicle where Dr Mutiso was seated.
The driver then drove directly to Kenyatta National Hospital seeking medical assistance. Dr Mutiso was subsequently pronounced dead.
The DCI said the investigation was initially handled by DCI Kilimani before being taken over by the Homicide Investigations Bureau, supported by forensic experts and other specialised teams.
The agency said forensic examinations, CCTV analysis and intelligence-led investigations subsequently led detectives to several suspects.
Two Main Suspects Identified
The DCI named Daniel Mwangi Njoroge and Kelvin Ngugi Kinuthia as key suspects in the investigation.
According to the statement, Njoroge was identified as an alleged organiser of the operation and was linked to one of the Toyota Prado vehicles allegedly used during the incident.
Kinuthia, meanwhile, was described by investigators as the alleged rider who transported the shooter to the scene.
The DCI said the investigation also established that two Toyota Prado vehicles had been hired shortly before the incident and that tracking information placed them at the scene.
These claims remain part of an ongoing criminal investigation and should be distinguished from findings that have been established through a final court determination.
DCI Links Serving Police Officers to the Investigation
One of the most significant revelations in the DCI statement was the alleged involvement of serving police officers.
The agency identified IP Kenneth Kipkemboi Sang, described as the Officer-in-Charge of Nderi Police Post under Kikuyu Police Station, as an alleged link between financiers and the operational team.
The DCI further alleged that Sang was connected to the source of the firearm used in the killing and said he was on the run.
Another officer, PC Elijah Kibelion Kimoi, attached to Karinde Police Post under Kikuyu Police Station, was said to have been arrested. The DCI alleged that Kimoi was the individual identified through the investigation as having fatally shot Dr Mutiso.
A third officer, PC Bett Kiplangat Collins, of Thogoto Police Post, Kikuyu Police Station, was also mentioned in the statement. The DCI said he had been forensically placed at the scene and was on the run.
The agency described the alleged involvement of serving officers as a serious betrayal of public trust and said it would pursue those implicated.
Gachagua Challenges the DCI Account
Following the release of the DCI statement, Gachagua issued a strong response on Facebook.
Rather than accepting the DCI's account, the former Deputy President accused the agency of attempting to shield police officers allegedly involved in Dr Mutiso's death.
“Bwana DCI, I have seen you have called a press conference to cover up the police killers of Dr Victoria Nthunya Mutiso and then fix some boda boda riders.”
He further claimed that he had information identifying three police officers whom he alleged were responsible for the killing.
“I have the names of the three police killers from Murkomen’s community whom you have been instructed to cover up.”
Gachagua warned that he would release further details if he believed the DCI press conference amounted to a cover-up. He specifically challenged the DCI to identify what he described as an inspector from Kikuyu Police Station, a constable from the same station and another constable from Karinde Police Post.
“You must name the inspector from Kikuyu Police Station, the constable from the same police station and the other constable from Karinde police post.”
Gachagua also claimed that serving officers had provided him with information about the case.
“Good officers have given me all the details and your days of covering up killings by police officers must come to an end.”
His remarks represent serious allegations against the DCI and other individuals. They should therefore be understood as claims made by Gachagua rather than independently established facts.
Call for ‘Sierra’ Officers to Speak
Gachagua went further by calling on what he described as the Nairobi Sierra killer squad to appear publicly and explain their side of the story.
He alleged that members of the group had been transferred out of Nairobi and claimed they could provide information about people who allegedly instructed them.
“Also, bwana DCI, allow the Nairobi sierra killer squad you have transferred out of Nairobi to attend the presser. They want to tell Kenyans and name the persons who have been instructing them and how they are now being victimized.”
The allegation introduces another dimension to an already sensitive investigation, although the claims about such instructions and alleged victimisation have not been established by a court.
DCI Points to Land Dispute as Possible Motive
The DCI statement also provided information about a possible motive. Investigators said the killing appeared to be connected to a longstanding land dispute involving Dr Mutiso.
According to the statement, Dr Mutiso had placed a caveat on a parcel of land identified as LR No. 1504/13 in Mlolongo, Athi River Sub-County. The DCI said the matter had been the subject of a civil case at the Machakos Law Courts.
Investigators further alleged that Rose Mbithie Mulwa and her son Christopher Mulwa, also known as Chris Mulwa, were among the alleged organisers and financiers of the conspiracy. The statement said the two had been detained following an application before the Chief Magistrate's Court at Milimani and that investigators had been granted additional time to complete their inquiries.
Again, these are allegations contained in an ongoing investigation and should not be treated as proof of criminal responsibility before the conclusion of court proceedings.
Investigation Remains Ongoing
The DCI said investigations into Dr Mutiso's death remain active. Investigators are pursuing additional leads and have indicated that they want to establish the role of everyone who may have participated in the alleged operation, whether as an organiser, financier, facilitator or otherwise.
The agency also said it was examining a possible connection between the suspects in the Dr Mutiso case and the 2025 killing of lawyer Kyalo Mbobu along Magadi Road. The DCI has urged members of the public with relevant information to come forward through established channels.
A Growing Public Debate
Summary of the Two Positions:
• DCI Position: Significant progress made through forensic/CCTV evidence, several suspects and serving officers identified and facing prosecution.
• Gachagua Position: DCI statement represents an incomplete picture and attempt to shield high-level individuals and specific officers.
The competing claims make it especially important for investigators to provide evidence that can withstand independent scrutiny and for any suspects to receive due process through the courts.
Dr Mutiso's death has attracted widespread attention because of her professional contribution to mental-health research and her role in the mental-health community.
The DCI has promised further updates as the investigation progresses. For now, the central question remains whether investigators will establish the full chain of events surrounding the killing and whether every person found to have played a role will ultimately be held accountable through the law.