The officer, who is in charge of a unit in the village of Roumieh, was bringing the sandwiches to a prisoner, Charbel Shalitta, who faces the death penalty for killing a young Lebanese man, The (Lebanon) Daily Star reported.
The officer said he was trying to protect himself from the prisoner, who is part of Fatah al-Islam, a radical Islamist group.
The sandwiches were filled with a chemical called carbure, made up of carbon, oxygen and a third element, that can be used in explosives.
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