The death toll in a fire which engulfed a shopping centre in Pakistan has climbed to 67, police have confirmed.

Police say 77 people are currently reported as missing by their families following the fire at Gul Plaza, in Pakistan's largest city Karachi, on Saturday evening.

But the scale of the damage following the blaze - which took more than 24 hours to put out - has slowed rescue efforts, as authorities comb the remains of the 6,500sq m (70,000 sq ft) complex.

While some of the bodies found are only partial remains, authorities had been able to count 67 skulls, the deputy commissioner of police told the BBC. The process to identify the bodies continues, with 15 people identified so far.

Gul Plaza had housed some 1,200 shops, spread across multiple floors. It is wedding season in Karachi, often a particularly busy time of year for shoppers.

While the cause of the fire is still unknown, witnesses earlier told the BBC that a lack of working fire exits and the density of shoppers and stalls crammed into the building exacerbated the disaster.

Shop owner Rehan Faisal recounted how it only took about "five to seven minutes" for everything to "burn before our eyes".

"Many customers and shopkeepers were coming up... and saying there was a fire downstairs. I was just beginning to comprehend the situation when the shop owner told me to lock up and get out," he told BBC Urdu.

With the facility due to close soon, most of the gates of the shopping centre were locked, witnesses said.

Senior police official Syed Asad Raza told Reuters news agency that all but three of the centre's 16 exits were locked.