Varanasi, Nov 28 : The Varanasi police have decided to initiate action under the National Security Act (NSA) against Sinku a.k.a. Ajay Kumar, who allegedly sexually assaulted a nine-year-old girl in the premises of a reputed private school in Varanasi. Deputy Commissioner of Police (DCP), Varuna Zone, Vikrant Veer said, "The accused was arrested on Friday after the incident. He will also be booked under NSA. Further investigation is underway in the matter." The minor girl, a student of Class 3, was sexually assaulted by Sinku, the sweeper of the school, when she had gone to school toilet on Friday morning. Finding her alone, Sinku sexually abused her. After coming home, the girl narrated the ordeal to her mother. On the complaint of the girl's parents, an FIR was lodged with the Sigra police under Section 376 of IPC and POCSO Act. Senior police officials went to the school and checked the CCTV footage. The DCP said that after the identification of the accused, eight teams of police were engaged to nab him. The accused was arrested within three hours on Friday, he said. Taking serious note of the rape case in the school, the Varanasi commissioner of police A. Satish Ganesh had set up a six-member special investigation team (SIT) led by the Deputy Police Commissioner, Varuna zone, Vikrant Veer to investigate the matter. /IANS