Six children are among the eight people who have been trapped all day Tuesday in a cable car dangling over a deep valley in Pakistan, with military helicopters hovering nearby ahead of a possible rescue attempt.

The children were using the chairlift to get to school when a cable broke at a height of around 1,200 feet (about 365 metres) midway through its journey in a remote, mountainous part of northwestern Khyber Pakhtunkhwa province.

"The evening is coming nearer. Tell us why the helicopters are going back?" Gul Faraz, one of the adults stuck in the cable car, said to AFP by phone. 

"For God's sake help us," he earlier told local media. 

Several military helicopters flew reconnaissance sorties and an airman was lowered by harness to deliver food, water and medicine, Tanveer Ur Rehman, a local government official, told AFP.

"This is a delicate operation that demands meticulous accuracy. The helicopter can not approach the chairlift closely, as its downwash (air pressure) might snap the sole chain supporting it," he said. 

Anxious crowds gathered on both sides of the ravine, which is several hours from any sizeable town. 

"Every time the helicopter lowered the rescuer closer to the chairlift, the wind from the helicopter would shake and disbalance the chairlift making the children scream in fear," Ghulamullah, chairman of the Allai valley area, told Geo News.

- 'What can they do?' -

The gondola broke down at around 7:00 am local time, with residents using mosque loudspeakers to alert neighbourhood officials across the Allai valley.

Headmaster Ali Asghar Khan told AFP by phone that the children were teenage boys and students at his government high school Battangi Pashto.

"The school is located in a mountainous area and there are no safe crossings, so it's common to use the chairlift," Khan said. 

"The parents are gathered at the site of the chairlift. What can they do? They are waiting for the rescue officials to get their children out. We are all worried."

Abid Ur Rehman, a teacher from another school in the area, said around 500 people had gathered to watch the rescue mission.

"Parents and women are crying for the safety of their children," he told AFP.

Syed Hammad Haider, a senior Khyber Pakhtunkhwa provincial official, said the gondola was hanging about 1,000 to 1,200 feet above the ground.

Caretaker Prime Minister Anwaar-ul-Haq Kakar issued a directive for all chairlifts in mountainous areas to be inspected and for those that are not "safety compliant" to be immediately closed.

Cable cars that carry passengers and sometimes cars are common across the northern areas of Khyber Pakhtunkhwa province and Gilgit-Baltistan, and are vital in connecting villages and towns in areas where roads cannot be built. 

In 2017, 10 people were killed when a chairlift cable broke, sending passengers plunging into a ravine in a mountain hamlet near capital Islamabad.

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