"We have arrested Arjun Sharma late on Monday night. He is booked under the IPC sections of murder and criminal conspiracy. We had registered an FIR against eight persons and investigation is currently underway," said Ashok Kumar Singh, SP of Araria.

Police said Vimal, who sustained gunshot injury on right side of chest, had died on the spot.

On August 19, Araria police had arrested four accused named Vipin Yadav, Bhavesh Yadav, Aashish Yadav and Umesh Yadav..

Bhavesh and Aashish, neighbours of Vimal Yadav, have been booked under IPC sections 302, 120B and 34 of IPC on the statement of the deceased's father Harendra Yadav.

Harendra had registered the FIR against eight persons and two of them Rupesh Yadav and Kanti Yadav are lodged in Supaul jail and Araria jail, respectively.

Rupesh, neighbour of deceased Vimal, hatched a conspiracy from Supaul jail where he is lodged in connection with the murder of Gabbu Yadav, the younger brother of Vimal.

Rupesh was threatening Vimal of dire consequences if he does not withdraw his name from the list of witnesses in the Gabbu Yadav murder case.