More than 1,300 Muslim pilgrims heading to Saudi Arabia for the annual Hajj are stranded at a Tanzanian airport.
Thursday is the last day set by Saudi authorities for millions of Muslim pilgrims to arrive in the country.
Air Tanzania had hired a plane that broke down. Its replacement has not been given a landing slot in Jeddah.
A BBC correspondent says the group, which has spent 10 days at Dar es Salaam airport is not angry and sees the setbacks as a test of faith.
"Anyone who gets angry because of flight delays at this time of year does not know Islam," one Tanzanian pilgrim told the BBC.
Most of the pilgrims are Tanzanian, although several hundred come from the Democratic Republic of Congo and Comoros Islands.
The BBC's Vicky Ntetema in Tanzania says the pilgrims were supposed to leave on Monday 3 December.
On Tuesday, a replacement plane was about to leave with 600 people aboard.
The passengers boarded the plane at 2000 local time but had to disembark at midnight after Saudi air traffic control could not provide a landing slot for the aircraft.
This proved the last straw for three women overcome with heat and emotion who had to be taken to hospital.
The Tanzanian pilgrims have had to rely on local Muslims for food and water during their long wait.
Those from DR Congo and the Comoros have been put up in hotels in Dar es Salaam.
Our correspondent says Air Tanzania is still hoping to get the pilgrims to Jeddah by the deadline.
The journey from Tanzania to Saudi takes about eight hours.
Every year about 2m Muslims converge on Mecca - the holiest place in Islam - for the Hajj.
Every adult Muslim is supposed to undertake the Hajj at least once in their life if they can afford it and are physically able. BBC