(ANSA) - BELGRADE, 08 OTT - A knife attack occurred at an elementary school in Leszczydół-Nowiny, near Wyszków, Poland, killing a woman and injuring two others. According to police, the attacker is a 15-year-old boy who was a former student at the school and is currently in police custody. According to authorities, the boy entered the school at 9 a.m. with a knife and injured three staff members, including the 37-year-old woman (identified by media as a school custodian) and the principal, who apprehended him. Despite resuscitation attempts, the woman died, according to police. This latest incident follows a similar knife attack yesterday at a school in Ostrołęka, Poland, which injured seven people. (ANSA).