杭州警方通报女子误踩氢氟酸中毒身亡，涉案人员已被控制

Group 1 - The incident involved a woman named Tu, who accidentally came into contact with hydrofluoric acid, leading to her unfortunate death [1] - The investigation revealed that Tu was in the area to cultivate land with friends when she stepped on a plastic barrel containing hydrofluoric acid, resulting in severe pain [1] - Two additional similar barrels were found at the site, indicating a history of improper disposal of hazardous materials by a previous resident [1] Group 2 - The involved parties have been detained, and the case is under further investigation by the authorities [2]