The only US flag not captured or lost during George Armstrong Custers Last Stand at the Battle of Little Bighorn in south eastern Montana has been bought at auction on a bid of 2.2 million US dollars. The frayed 7th US Cavalry flag - known as a guidon for its swallow-tailed shape - was sold at Sothebys auction house in New York. Belfast The seller was the Detroit Institute of Arts, which bought the flag for just 54 dollars (34) in 1895. The buyer was not immediately known. Custer and more than 200 troopers were massacred by Lakota Sioux and Northern Cheyenne warriors in the infamous 1876 battle. Of five guidons carried by Custers battalion, only one was immediately recovered. The flag had been valued at 2 million to 5 million US dollars. Belfast