Italian authorities have this evening issued an appealed to pilgrims to stay away from the centre of Rome, saying it was saturated and any newcomers would have no chance of seeing Pope John Paul's funeral on Friday.
Guido Bertolaso, head of crowd control for the funeral, told reporters well over one million people had already flocked to Rome, whose normal population is around 3 million.
"The city centre cannot take the arrival of any more faithful," said Mr Bertolaso. "Anyone arriving tonight or tomorrow will have no possibility of following the funeral at St. Peter's."
Rome police chief Achille Serra said: "The number of people is staggering and is growing constantly. This is unprecedented."
As night fell, Rome faced paralysis from the influx of pilgrims and authorities said they would not allow anyone else to join the lines from 10 pm (9 pm Irish time) - almost a day ahead of schedule - so that the crowds could pass through St Peter's Basilica ahead of the funeral.
Security officials shut off the huge queue of people some of whom have been waiting up to 14 hours to see the Pope, and warned that any new pilgrims would not be able to reach the church.
New arrivals, coming in on planes, trains and buses from around the world, were urged to make their way to a special reception area in the suburbs of Rome.