Ten letters, which were obtained through a public records request, were “found in late November 2017 by the new owners of an abandoned office building in Mesquite, Texas,” according to FBI records, the newspaper reported. A friend of Stephen Paddock, who carried out the deadliest mass shooting in modern US history in Las Vegas in 2017, said in letters he was concerned about Paddock committing a shooting and asked him not to “shoot or kill innocent people,” according to writings obtained by the Las Vegas Review-Journal.