From The JPost:
Medicine bottles, transferred to the Gaza Strip as humanitarian aid by Israel, were used by Hamas as grenades against IDF troops during Operation Cast Lead. Pictures of the grenades were obtained exclusively by The Jerusalem Post.
The medicine bottles were manufactured by the Jerusalem Pharmaceutical Company, which is based in el-Bireh, a town adjacent to Ramallah, and the global pharmaceutical company Shire.
The medicine bottles were filled with explosives, holes were drilled in the caps, and fuses were installed. Once Hamas fighters lit the fuses, they had several seconds to throw the grenades at soldiers. The IDF also found small explosive devices that used medical syringes to hold their fuses.
The medical grenades were discovered in northern Gaza by troops during last month's three-week battle against Hamas. The grenades were taken to military explosives experts, and then disassembled and studied.