I personally count the Banana's massacre, which resulted in an estimated 2000 protesters dead. While the shooting was made by Colombian soldiers instead of US soldiers, it was a direct result of the US Goverment's threat of invading Colombia if the protest done by United Fruit Company workers was not inmediately put to a stop.
EDIT: I think the above comment is a misleading. A better description of the massacre is that it was done to serve US economical interests, aided by US's military pressure (like US officials asking US army forces to send a warship into the zone) and a possible risk of invasion from US into Colombia's mainland. I also think a possibly more accurate number of protestors dead is ~1500. I do stand on the opinion that the massacre was a direct consequence of US Government, simply perpetrated by Colombian soldiers.