A report credited to The Punch revealed operatives of the DSS interrogated him 11 different times since May over crude oil swap deals with traders.

Diezani Allison-Madueke, Nigeria’s immediate past minister of petroleum
He was quoted as telling Reuters that the DSS has been harassing some of them over the oil swap deals with traders.
The reports stated further that the investigation by the DSS and anti-graft agencies involved crude oil swap deals and offshore processing agreements in which the corporation gives certain volume of crude oil to traders in exchange for refined products.
And instead of ensuring that crude oil was made available to the nation’s four refineries for domestic consumption, the immediate past minister of petroleum resources, Mrs Diezani Alison-Madueke, in conjunction with the Pipelines and Products Marketing Company, reportedly increased the crude oil swaps and OPAs from 270,000 barrels per day to 445,000 bpd, thus starving the refineries of crude oil.
Fuel Scarity To Hit South West Nigeria
President Muhammadu Buhari, in his bid to overhaul the corporation, ha instructed the NNPC to review the crude for oil products swap contracts and offshore processing agreements with trading companies because of the belief that the deals might have cost the country millions of dollars in lost revenue and refined product supply.
And this may have been followed up by the security agency with the grilling, a development which the corporation is not totally comfortable with.
“The DSS has been harassing some of us. There is a siege mentality here at the moment,” Udoh, an NNPC veteran of 36 years lamented.
He added that Buhari’s initiative had given fresh legs to media coverage of the accounting holes worth over $20bn identified by two separate investigations, and that the public pressure was dominating management meetings.
Soldiers are said to be guarding the building of the headquarters of NNPC in Abuja as the DSS operatives are closely monitoring the affairs of the corporation, while visitors were required to go through four separate security checks.
President Buhari had instructed the NNPC to review agreements behind the programme to swap crude to refined products, just as Mallam Nasir El-Rufai has clamoured for the death of the corporation.