mexico city twelve people die 18 injure tuesday mexico state quintana roo tour bus lose control roll excursion ancient ruin bus carry 31 passengers include citizens unite state brazil sweden authorities say child among dead quintana roo one three state mexico yucatan peninsula popular tourist sit twenty-seven passengers travel royal caribbean cruise ship spokeswoman cynthia martinez say hearts go involve bus accident martinez say statement care guests include assist medical care transportation tourists head archaeological zone chacchoben ancient mayan ruin south resort town tulum vehicle veer highway early tuesday accident passengers take hospitals bus company costa maya say statement five discharge injure stable condition say government quintana roo say statement investigate cause accident u.s. embassy mexico say work authorities learn whether u.s. citizens aboard bus last year 11 tourists kill crash quintana roo bus flip en route cancun associate press report least 12 dead bus crash excursion mexican ruin