It was gathered that the 7B Apartment was bought in the name of a company allegedly owned by the wife of a senior government official.
The individuals were said to have been invited for questioning after the anti-graft agency found that some of the occupants of the Towers were involved in moving the cash into the controversial apartment 7B.
According to The Nation, the EFCC has also identified how the apartment was acquired and in whose name it was bought.
The EFCC operatives had last Wednesday recovered $43.4m, £27,000 and N23m cash from the apartment.
"The more we investigate this $43.4m haul, the more we get fresh facts. It has become imperative to interact with some owners or tenants of apartments in the Towers," a source at the EFCC told the newspaper.
"We have invited a former governor and other high-profile owners and tenants for interaction. It is just to ask a few questions on whether or not they were aware of such movement of cash.
"We have clues linking some occupants of the Towers to the cash haul. And in line with sections 16 and 17 of the EFCC (Establishment Act) 2004, we are inviting these landlords or tenants.
"Unless we get to the root of this case, Nigerians may not know the truth or otherwise about the cash.
"We are not saying that those invited are guilty of any infraction or having link with the $43.4million but we need to hear from them – in line with the ongoing profiling of those in the Towers," the source said.
Another source said the ongoing investigation also revealed that the 7B Apartment was bought in the name of a company allegedly owned by the wife of a senior government official.
"Since investigation is still ongoing, we will not release the identity of the owner of the company. Doing so might jeopardise investigation," the source said.
However, the National Intelligence Agency (NIA), insists the cash haul and the apartment in question belong to the agency.
"What happened was that because of the nature of the covert operations which the apartment will be used for, it was necessary to manage the process well," a source at the NIA was quoted as saying.
"Only the Deed of Assignment was acquired by Thabis Ventures Limited on behalf of NIA. And immediately the process for the purchase of the apartment was completed, the ownership was clearly stated in the name of NIA. All the papers are reflecting NIA too. The title document is available for anyone to verify," the source said.
SaharaReporters had reported on Tuesday that the haggard-looking woman who pretentiously moved cash-bags into the apartment turned out to be the wife of the NIA director.
Initial reports had said the woman would dress shabbily but her glowing skin and accent made guards at the towers believe that her appearance may be a disguise.
It is, therefore, believed that she is the 'wife of a senior government official' mentioned by the EFCC source.