The Dhanusa District Police Office said that Sah, who was elected from Dhanusa-4, is the “mastermind” of the blast at Ramanand Chowk in Janakpur on April 30 2012, killing five people and injuring 32 others.

The former State Minister for Physical Planning and Works, Sah, is the only directly elected lawmaker of Nepal Sadhbhawana Party in the second CA election.

Superintendent of Police Uttam Subedi said there are many “supporting documents” that suggest Sah’s involvement in the blast.

“We are searching him,” he said.

Police had arrested chief accused of the blast Mukesh Chaudhary from Nagarin VDC-9 in the district on March 2. Chaudhary in his statement to police revealed the involvement of Sah in the blast, SP Subedi said.

Subsequently, police arrested Om Prakash Yadav, once a close aide to Sah and who had joined the Nepali Congress during the second CA election. Yadav has also confessed to police the  involvement of Sah in the blast.  

Earlier, police had taken Jay Prakash Chaudhary, Suresh Kumar Karna, Jitendra Lal Karna and Ripendra Jha under custody for further investigation.