Akal Takht Jathedar Giani Raghbir Singh on Wednesday asked the Centre to clarify its position on Canada's allegations about the murder of a Khalistani terrorist, Hardeep Singh Nijjar. "This has left the Sikhs living across the world shaken and has reminded them of Operation Blue Star," Giani Raghbir Singh said. Akal Takht is the highest temporal seat of Sikhs.