7.17pm Thursday (1717 GMT): The Pope receives the sacrament for the sick and dying, a Vatican statement says.
Thursday afternoon: The Pope's clinical situation stabilises temporarily, a Vatican statement says.
10.13pm: Italy's APcom news agency reports the Pope's condition has worsened because of a "worrying lowering of [blood] pressure".
10.22pm: A Vatican statement says the Pope is suffering a high fever because of a urinary tract infection on Thursday afternoon.
5.43am Friday: A Vatican statement says the Pope's condition on Friday morning is "very serious" and that he suffered septic shock and cardiovascular collapse on Thursday afternoon.
6am: The Pope celebrates Mass, a Vatican statement says.
7.15am: The Pope asks that the 14 stations of the Way of the Cross be read to him.
12.30pm: A Vatican spokesman tells a news conference the Pope is conscious and has been "informed of the gravity of his situation".