Simplify the following text for a Grade 8 native English-speaking person.
Original: Escopetarras were invented by Colombian peace activist CÃ sar LÃ pez in 2003 at a gathering after the El Nogal Club bombing in BogotÃ , when he noticed a soldier holding a gun like a guitar .
Simplified: Escopetarras were invented in 2003 by a Colombian peace activist named CÃ sar LÃ pez . At a gathering after the El Nogal Club bombing in BogotÃ , he noticed a soldier holding a gun like a guitar and got the idea for it .