Police on Friday evening arrested 52-year-old Gyanshankar Sainju, a resident of Kathmandu metropolitan city-28 Dhobidhara on the charge of knife attack. Sainju reportedly attacked 25-year-old Pankaj Achhami Magar residing in the same area with a knife. Magar, originally from Kamalamai municipality-4 in Sindhuli sustained serious injury in the attack and is undergoing treatment at Trauma center in Kathmandu. Police are further investigating on the incident.