Pope John Paul II is in "very serious condition" after suffering a septic shock and a heart attack, Vatican officials said on Friday.
At 2247 GMT on Thursday, he received the Saint Viaticum, the rites administered to the ill when approaching death.
The sacrament is called Extreme Unction or Last Rites; it was renamed to reflect its administering not only to the dying but to the sick, as well.
"This morning (Friday) the health of the Holy Father is very serious," Vatican spokesman Joaquin Navarro-Valls said.
The 84-year-old Pope is "conscious, lucid and serene", he added.
The pope was immediately given "the appropriate cardio-respiratory assistance," Navarro-Valls said.
He had developed high fever due to a urinary tract infection.
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