Former Kaduna State Governor, Malam Nasir El-Rufai, has written to the National Security Adviser, Nuhu Ribadu, requesting clarification over reports that the Office of the National Security Adviser (ONSA) imported about 10 kilograms of thallium sulphate, a highly toxic substance.

In a letter titled “Request for Clarification on the Procurement of Thallium Sulphate,” El-Rufai said he was seeking reassurance “as a concerned citizen” over the alleged procurement, reportedly from a supplier in Poland.

He asked Ribadu to clarify the intended use of the substance, the identity of the supplier, import permits, storage arrangements, and regulatory oversight involving agencies such as National Agency for Food and Drug Administration and Control and Nigeria Centre for Disease Control.

“I want to stress that this inquiry is made in good faith, solely to ensure that due processes, safety standards, and transparency are observed,” El-Rufai wrote.

The development follows recent controversy over El-Rufai’s claim that Ribadu was involved in an attempt to arrest him at Nnamdi Azikiwe International Airport.

Speaking on ARISE Television, El-Rufai alleged that Ribadu ordered the move and said he became aware after the NSA’s phone was tapped by an unnamed source.

“The government believes it is the only one that listens to calls, but we also have our ways,” he said.

El-Rufai, who has accused the current administration of witch-hunting, also confirmed he will honour an invitation from the Economic and Financial Crimes Commission following his return from overseas.