Investigat□rs □earned that t□e group ha□ b□en f□iend□ for years, but rec□□tly there had □een □ension amo□g □hem. R□m□rs of disagreements an□ □rgument□ du□□n□ the□trip began to sur□a□e, leading au□hor□ti□s to □peculate wheth□r fou□ play was involved. Each mem□e□ of the group □ad □ d□ffer□nt story to □ell, and□t□e□□nc□□siste□cie□ in t□eir□acco□n□s only added□to the mys□□ry of the mis□ing ni□e.