India, May 22 -- The investigation into the murder of West Bengal chief minister Suvendu Adhikari's close aide Chandranath Rath took a dramatic turn this week after the release of a person Central Bureau of Investigation (CBI) "mistakenly" arrested, sparking reaction from political leaders, who called the man wrongly held man "devotee" of the Bharatiya Janata Party (BJP).

Raj Singh, 28, was arrested on May 10 by the West Bengal Police Special Investigation Team (SIT) formed to probe the case. The CBI took over the case investigation after registering a separate FIR in the matter on May 11.

Singh was released from Kolkata on May 20 after the CBI found he had been mistakenly detained due to confusion over his name with that of the alleged...