Within weeks of the news spreading about the discovery of gold, silver, copper or other valuable minerals, thousands of prospectors would arrive in an area creating a "boomtown." Mining towns were often overcrowded, ramshackle towns with tents, saloons, a bank and other small businesses filled with gamblers, gunslingers, claim jumpers, and outlaws. Vigilante groups were formed to deal with outlaws. Many of the boomtowns were located near or within Indian reservations. This led to numerous conflicts with the native tribes of the West. Boomtowns were often abandoned and left as ghost towns once the minerals ran out.