A passenger train crashed into a bus carrying Sikh pilgrims at an unmanned railway crossing in eastern Pakistan on Friday, killing at least 22 people and injuring several others, officials said.

The accident happened in the district of Sheikhupura in Punjab province, Raja Ijaz, an official at the state-run emergency service, said. Ghazi Salahuddin, district police chief, said the dead and injured were transported to a nearby hospital.

Officials said the Sikh pilgrims were from the northwestern city of Peshawar and were returning from the shrine of Nankana Sahib in Sheikupura.

Asghar Joya, a government official in Sheikhupura, said an initial assessment indicated the bus driver tried to cross the railway track as the train neared but the vehicle slid and got stuck. He said, however, that officials were still investigating.

TV footage showed the train and the badly destroyed bus on the railway track.

Sheikhupura resident Dilbir Singh said the pilgrims were returning to Peshawar when the accident happened. He said that prior to leaving for Peshawar they visited the home of a relative whose family member had recently died.

Pakistan's President Arif Ali and Prime Minister Imran Khan in separate statements expressed deep sorrow over the accident and ordered authorities to provide the best possible treatment to the injured.

Sikhs have several shrines of their religious leaders in Pakistan. One, of Sikh founder Guru Nanak, is located in Pakistan's Kartarpur bordering India in Punjab. It was built after he died in the 16th century.

Many Sikh holy sites became part of Pakistan after the British partitioned the subcontinent into India and Pakistan in 1947 after two centuries of colonial rule.

Ties between the hostile neighboring countries deteriorated sharply after India revoked the disputed Kashmir region's semi-autonomous status in early August.

Train accidents are common in Pakistan, mainly due to lack of enforcement of safety standards, a poorly kept railroad system and automobile driver negligence. In February, a train crashed into a bus carrying passengers at an unmanned railway crossing in Rohri district in southern Pakistan, killing 19 people and injuring 28 others.
Last November, a fire caused by a cooking gas stove swept through a train in Pakistan's eastern Punjab Province, killing 74 people. Survivors at the time said that it took nearly 20 minutes for the train to stop amid contradictory reports about the condition of the train's brakes.