International Desk

At least 28 Pakistani pilgrims travelling to Iraq for a Shiite Muslim ritual were killed as their bus crashed in central Iran, state media reported early Wednesday.

"A bus carrying 51 Pakistani pilgrims overturned and caught fire in front of Dehshir-Taft checkpoint in the central province of Yazd on Tuesday night," Iranian state television reported.

It said "28 people have been killed and 23 injured so far with the possibility of the death toll increasing".

Yazd province crisis management chief Ali Malek-zadeh told the broadcaster that some of the injured were in critical condition.

"Of the 23 injured, six have already been discharged from hospital, while the condition of seven others is critical," Malek-zadeh said, reports AFP.

"The dead consisted of 11 women and 17 men," he added.

Head of Iran traffic police, Teymour Hosseini, cited "technical failure in the brake system" and the "high inclination of the road" as the reasons for the crash.

The Iranian and Pakistani foreign ministries expressed their condolences and sympathies to the families of the bereaved.

Pakistan's Foreign Office further said the consul of Pakistan in Zahedan has been asked to visit the accident site to ensure medical relief to the injured and arrange the repatriation of the dead bodies to Pakistan.

Most of the victims are residents of Pakistan's southeastern Sindh province where the bus journey began.

Syed Sultan Ali, the brother of the tour operator, told AFP: "My older brother Syed Shamsi has been running this service since 2010, and it has always gone so well. We have been deeply upset since last night."

He added that his brother is "unhurt" because he was travelling in a separate vehicle.

The Pakistani pilgrims were headed through Iran to Iraq to attend the Arbaeen commemoration, one of the biggest events of the Shiite calendar which marks the 40th day of mourning for Imam Hussein, the grandson of the Prophet Mohammed.

Last year, some 22 million pilgrims attended the commemoration in the Iraqi shrine city of Karbala, where Hussein and his brother Abbas are buried, according to official figures.