In a letter, detective Michael Sang directed Matiang'i to appear before him at Mazingira House at 9.30 am without fail. However, Dr Matiang'i through his lawyers, responded that he was out of the country and could not attend the summoning.
"I have reasons to believe that you, Dr Fred Matiang'i, the former Cabinet Secretary, Ministry of Interior and National Co-ordination, is connected to the offence or have information which can assist me in my investigation," the letter read.
The detective's letter follows a purported and widely reported raid at the CS's home which the police said never occurred and sought CCTV footage from his home to verify the claims.
A few days later, security officers forcefully entered the residence on February 15 and ransacked the house.
A senior officer at the DCI said that the summon was still on and they were only waiting for the former CS to come back.
Last week, Dr Matiang'i troubles deepened when it emerged that the anti-graft body was pursuing his wealth.
The EACC has written to the Head of Public Service seeking information on how much was Dr Matiang'i worth when he took office as Cabinet Secretary under former President Uhuru Kenyatta's government in 2013.
In a letter dated February 27, 2023, and signed by the EACC chief Executive Officer Twalib Mbarak noted that they were interested in the former CS's wealth pursuant to Section 30(1)(4)(b) of the Public Officers Ethics Act.
"The Commission wishes to request for Certified Copies of Declaration of Income, Assets and Liabilities forms for years 2012 to 2022, including the initial and final declarations," reads Mbarak's letter.
Mbarak said the Anti-corruption body was carrying out investigations on Dr Matiang'i.
"The Commission is carrying out investigations involving Dr Fred Matiang'i, former Cabinet Secretary for Interior and Coordination of National Government," said Mbarak.
The EACC boss said their officers Mr Abdul Low and Mr Paul Mugwe were available to collect the documents.
During the 10 years of Uhuru's two terms, Dr Matiang'i served as CS for Information and Communications Cabinet Secretary in 2013.
He was later moved to Education, Science, and Technology in December 2015 having previously been in an acting capacity as the Cabinet Secretary for Lands.
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He was later transferred to the Interior Ministry in 2017 and elevated a year later to chair of cabinet sub-committee meetings.
As the EACC was writing to him, another letter from the Immigration Department to the Director of Criminal Investigations (DCI) dated February 28, 2023, revealed details of when former Interior CS Fred Matiangi left the country and the triangulation of his travels in the recent past.
The letter signed by Emmanuel Simiyu, for the Director General of Immigration indicated that Dr Matiang'i left the country a week before he was summoned.
"The subject departed on February 19, 2023, through JKIA on KLM flight number KL566," read the letter.
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