A bus carrying pilgrims to Mecca, Saudi Arabia, caught fire after a collision on a bridge on Monday, killing 20 people and injuring around 30 others, state television reported.

The accident, in Asir province (south), highlights the ongoing challenge of transporting pilgrims to Mecca and Medina, the two holiest cities for Muslims.

It is recorded in the first week of the month of Ramadan, when many Muslims perform the (‘small’) Umrah pilgrimage, and a few months before the (‘major’) annual Hajj pilgrimage.

“Based on initial information, the death toll in the accident has reached 20, and the total number of injured is around 30,” Saudi Al-Ikhbariya TV reported.

The victims were of “various nationalities,” according to the same source, which did not provide further details.

Al-Ikhbariya aired footage showing its reporter in front of the charred corpse of the bus.

Transporting pilgrims on Saudi Arabia’s road network can be dangerous, especially during the Hajj, when buses full of worshipers form endless traffic jams.

In October 2019, 35 foreigners were killed and four others injured when a bus collided with a heavy vehicle near Medina.

Muslim pilgrimages are the engine of tourism in Saudi Arabia, a sector relied on by the kingdom’s political leadership as it seeks to diversify its economy, which is critically dependent on fossil fuels.