Twelve people who died during a religious ceremony were the victims of accidental carbon-monoxide poisoning, the state government said Friday.
"They fell asleep thinking they were in a trance," said Baja California state spokeswoman Sara Yolanda Gonzalez.
Autopsies completed Friday on the 12 men, women and children whose bodies were found Thursday showed that they died from carbon monoxide, a state government news release said.
"They had no electricity, only a gas lamp," Ms. Gonzalez said. "It consumed all their oxygen, and they had no windows open."
She said the deaths were not related to the religious ceremony that brought the people together at the home in the U.S.-Mexico border city of Tijuana on Wednesday night.
"They had an altar to the Virgin of Guadalupe, candles and holy water, and they chanted The Lord's Prayer," Ms. Gonzalez said.
A team of investigators discarded notions that the worshipers were followers of the devil, the state news release said.
Five people who survived the religious meeting remained hospitalized Friday, all in comas. The state had said Thursday that seven people were hospitalized but revised the figure to five Friday, saying the earlier number was an error.
Jaime Sam Fierro, Tijuana state judicial police commander, said Wednesday that the group practiced spiritualism, a religion practiced by many Christians in Mexico. Spiritualism involves passing into trancelike states to consult with spirits of the dead.