Thiruvananthapuram: The Central Bureau of Investigation (CBI) team investigating the SNC Lavalin pay off case on Wednesday inspected the residence of N. Sasidharan Nair, currently special private secretary to Minister for Industries Elamaram Karim. The surprise check which commenced at 4.30 a.m. concluded in the afternoon. Mr. Sasidharan Nair was special officer of the Malabar Cancer Centre in Kannur when the SNC Lavalin deal was finalised by the State Government. He lives at Kalpaka Gardens near Pappanamcode. The Canadian firm had offered Rs.100 crore as aid to the cancer centre in reciprocation for being awarded the contract for renovating the Pallivasal, Chenkulam, Panniyar hydroelectric projects. The CBI team reportedly recovered several key correspondences and documents crucial to the investigation.