More details have been revealed about the deaths of four Iowans while vacationing in Mexico. Amy & Kevin Sharp, and their children, Sterling & Adrianna, of Creston, were found dead inside their luxury condominium near Tulum on March 23.

Initial autopsies show the family of four died of asphyxiation from propane inhalation. Christopher Martinez, the primary investigator on the case, told the Des Moines Register that a rusty water heater caused the propane leak.

Each parent was found in a separate bedroom--both apparently had been sleeping--and the children, Sterling (12) and Adrianna (7), were found in front of the television in the living room.

Police do not believe there was any foul play. The apartment showed no signs of a break-in or struggle, and the bodies were undisturbed.