After weeks of dilly-dallying, police on Thursday said they have registered an FIR against Samajwadi Party chief Mulayam Singh Yadav for allegedly threatening an IPS official.Police, however, said the FIR was registered on September 24 but was not "declared".The FIR was registered on charges of criminal intimidation under relevant sections of the Indian Penal Code against the Samajwadi Party chief for threatening Indian Police Service officer Amitabh Thakur over telephone on July 10.On September 14, Chief Judicial Magistrate Som Prabha Mishra had directed the registration of an FIR under appropriate sections.On Wednesday, in the Lucknow bench of the Allahabad High Court, the Uttar Pradesh government had assured the bench of Chief Justice D.Y. Chandrachud and Justice S.N. Shukla that if the FIR has not been registered so far, it shall be registered forthwith.