Authorities imposed restrictions in parts of the city here on Saturday to prevent separatist-called protests against civilian killings during gunfights between security forces and militants.Prohibitory orders were imposed in Rainawari, Khanyar, Nowhatta, M.R.Gunj and Safakadal in old Srinagar and Maisuma and Kralkhud in uptown areas by the Srinagar District Magistrate."Essential services, government employees, bank staff, students appearing for examinations and the invigilation staff for such exams are exempted from the restrictions," the police said.The Joint Resistance Leadership (JRL) -- a separatist conglomerate headed by Syed Ali Shah Geelani, Mirwaiz Umer Farooq and Yasin Malik called for valley-wide shutdown and protests. Authorities placed Umer Farooq under house arrest in his Nigeen residence on the outskirts, while Geelani continued to remain under house arrest in his uptown Hyderpora residence.Heavy deployments of police and paramilitary Central Reserve Police Force (CRPF) have been made to maintain law and order at sensitive places in the city.Educational institutions, including universities, colleges and schools are closed in the Kashmir Valley due to winter vacations.