According to sources, CM Vigilance arrested Executive Engineer of Lakhra division, identified as Seemantajyoti Baruah.
He was arrested from Anand Nagar in Guwahati.
Baruah has been taken for a medical examination and will be kept in police custody at Panbazar Police Station.
The engineer was on a run since October 21 in fear of arrest.
Meanwhile, one more accused, identified as Mithu Agarwala, is still on the run.
CM Vigilance Superintendent Raji Kalita said that Mithu will be caught soon.
A total of 13 people have been accused in connection to the scam.