The suspect, 82, fled after the act on his wife of 59 years, Beatrice.
The 70-year-old woman was a retiree of the Imo State Polytechnic in Umuagwo.
In a chat with the News Agency of Nigeria (NAN) on Monday, the source in Imerienwe, said Okere had been suffering from dementia.
The source disclosed that the family had been managing the former IBC boss’s condition for some time.
“The other Sunday, Okere went to church and said that his car was missing when in fact the car was parked in his compound,” it added.
Police spokesman in Imo, Orlando Ikeokwu, confirmed the incident.
He said the command had commenced investigation into the matter.