By Steve Gorman LOS ANGELES (Reuters) - Two of America's biggest commercial brands - discount retailer Target and fast-food chain McDonald's - have taken steps to tamp down hysteria stemming from a recent spate of creepy clown sightings in the run-up to Halloween at the end of this month. Target decided last week to winnow down its assortment of clown masks and costumes available for sale in U.S. stores and online "given the current environment," company spokesman Joshua Thomas said on Monday. Although Target received some isolated consumer comments about scary clown accessories, the decision to pull some masks from inventories stemmed from "a conversation internally about how we can respond to the situation at hand," Thomas told Reuters.