HYDERABAD: A watchman was attacked by two sisters, one of them even slashed him with a knife, following an argument at an apartment complex in Ramakrishna Colony in Kukatpally in the early hours of Sunday. The entire drama was captured by a CCTV camera set up by a neighbour in the common area.The two sisters are daughters of retired sub-inspector S Ratnam and are suspected to be `mentally disturbed'. Cyberabad police said that Buchaiah (50), who is the watchman at Sri Sai Bharadwaj Apartment , ended up having an argument with the two women while checking a complaint from a resident about some noise in the building around 2.30am.Buchaiah, who was on the ground floor, started to check each floor. When he reached the third floor, he found the door of the flat (302) where the two sisters -Sailaja and Sunitha, who are in their early 30s -stay, ajar. On seeing the watchman, the two women started questioning him on why he had come up at such an odd hour. Within a few minutes, the sisters got aggressive and refused to listen to any explanation from the watchman. At that moment he got a call and as he was heading towards the stairs to go the next floor, one of the sisters lunged at him with a knife.“The two sisters were upset with him for checking at 2.30 am. The watchman called up the complainant while staying in the common area of the third floor, informing that he could not see any disturbance. But his loud voice angered the sisters who wanted him to leave the place immediately. When the watchman was about to take the stairs, he was stabbed in the buttocks by one of the two sisters with a knife,'' assistant commissioner of police (Kukatpally) N Bujanga Rao told the media.In the CCTV footage aired by some news channels, one could hear the two sisters saying: “Go and talk after going downstairs''. The visuals show the watchman moving away and in the next instant one of the sister can be seen coming behind him with a knife and attacking him. The woman who had attacked the watchman then pushes the watchman, but he manages to hold on to the railing. Buchaiah, who was in a dhoti, starts to bleed and stains can been seen on the dhoti in the CCTV footage. Later, the other sister can be seen throwing water on the CCTV , which was kept by their neighbour in the common area.Buchaiah, who was shifted to Ram Dev Hospital , was reported to be stable after a surgery to stop the bleeding.“It appears that the two sisters are mentally disturbed . Their father was supposed take them for treatment last week, but could not,'' the ACP said.The sisters, who stay with their father and brother in the flat, were yet to be arrested. They would be taken to hospital to ascertain their mental condition, police said.