(David Transier)A Southwest Airlines flight from San Diego heading to Chicago last night had to make an unplanned stop in Amarillo, TX, after police said a fight broke out on board among a group of passengers who were traveling together. The flight ended up diverting to Amarillo at around 10:30 last night, Southwest said in a statement (via the Associated Press), “after several passengers traveling together became disorderly and, subsequently, refused to obey instructions from the crew.” Once on the ground, six passengers were detained on suspicion of interfering with the flight crew, and six others deplaned at that time as well, as Southwest told CBS Chicago: “Additionally, six other members of the group chose to deplane and remain in Amarillo.” The AP reports that “a handful” of others were prevented from re-boarding the plane at the request of the crew, however, citing Amarillo police.