The case increased the level of concern expressed about levels of violence involving school-age youths, and the safety of pupils and staff while in school, which were beginning to become public issues in the United Kingdom in the early 1990s. This followed the fatal stabbing of 12-year-old Nikki Conroy by a mentally ill intruder at her Middlesbrough school in March 1994. In March 1996, 16 young children and their teacher were shot dead by intruder Thomas Hamilton at their school in Dunblane, Scotland. In July 1996, nursery nurse Lisa Potts and several toddlers were wounded by machete-welding intruder Horrett Campbell at a nursery school in Wolverhampton. These incidents all contributed to major improvements in security at schools across Britain, particularly in areas with high crime rates.