Three persons were arrested from Uttar Pradesh in connection with the killing of Chandranath Rath, an aide of West Bengal Chief Minister Suvendu Adhikari, police said on Monday.The accused were apprehended by the Special Investigation Team (SIT) constituted to probe the murder that occurred in North 24 Parganas district’s Madhyamgram on the night of May 6.Investigators traced digital clues and interstate links in the case, the senior police officer said.The arrested men were identified as Vishal Srivastava, a resident of Pandiyapatti in Bihar’s Buxar district, while the two others are from Uttar Pradesh, he said, adding that the investigators suspect that one of them is a sharpshooter.“This is a breakthrough. The investigation indicated that the assailants were from outside West Bengal. Based on technical surveillance, digital tracking and other inputs, members of the SIT were sent to Uttar Pradesh and Bihar,” the officer told PTI.At least eight people were involved in the conspiracy and execution of the murder, he said.The police believe that the attackers had carried out detailed reconnaissance before targeting Rath, he said.