Back in 1987, a liquor bottle filled with explosives and placed in a carry-on bag in an overhead bin helped terrorists crash a South Korean airliner. All 115 on board died.
Then, in 1994, Al-Qaeda member Ramzi Yousef, architect of the first World Trade Center bombing, detonated liquid nitroglycerin that he had taken on board a Philippine Airlines flight in contact lens solution bottles. One passenger was killed and several were injured in the incident.
In August 2006, a major terror plot was busted by the British police wherein terrorists plotted to detonate liquid explosives disguised as soft drinks carried on board airliners travelling from the United Kingdom to the US and Canada.
Source: Deccan Chronicle