Matthew Ziegler is an assassin whose overall mission was not revealed. His immediate objective was to recover a high-tech chip from several DEA agents that possessed the chip at one point or another. Ziegler committed mass murder on an early morning commuter bus, and assassinated a Federal Law enforcement agent in a crowded train station. He released an amber gas cannister on the crowded bus, killing eleven onboard and DEA Agent Evelina Mendoza. The gas caused the nitrogen in the air to solidify, immobilizing and suffocating fellow passengers like 'insects in amber'. Ziegler survived by donning a gas mask. He also collected all of the backpacks as he exited the back of the bus.