At least 30 people were killed and dozens injured Monday when a packed Pakistani inter-city train ploughed into carriages from another express that had earlier derailed, officials said.
An unknown number of people were still trapped in the tangled wreckage near Daharki in northern Sindh province, a railway spokesman said, adding rescue workers had called urgently for specialist equipment so they could be reached.
"The site is far and that's why we are facing some trouble in the rescue work, he said, adding at least six wagons were destroyed in the accident.
The spokesman said the accident happened when the Millat Express heading from Karachi to Sargodha, derailed before dawn, spilling onto a track carrying the Sir Syed Express from Rawalpindi in the opposite direction.
At least 22 people had been killed and up to 50 wounded, the railway spokesman said, while Umar Tufail -- a senior police officer at Daharki -- put the toll at 30 people had been killed.
Prime Minister Imran Khan said he was "shocked" by the accident and promised a full inquiry.
"Ordering comprehensive investigation into railway safety faultlines," his official Twitter account said.
Mobile phone footage shown on television from the site showed mangled wreckage, with several green Pakistan railway carriages lying on their side.
The accident happened in a remote part of the province on a raised section of track surrounded by lush farmlands.
