Switzerland. Canton Ticino. Melano. Ticino State Police, Reparto Intervento Speciali. Special Intervention Unit (SIU). SIU men check their special blue pistols used only during training exercices. The handguns are loaded with non lethal bullets in order to use them and shoot during training interventions. A police tactical unit (PTU) is a specialised police unit formed and trained to handle situations that are beyond the capabilities of ordinary law enforcement units because of the level of violence - or risk of violence - involved. 18.02.22 © 2022 Didier Ruef