Iran’s interior minister has said negligence was a factor in the massive explosion and fire at the country’s largest container port, as the death toll rose to at least 70.

Eskandar Momeni said Saturday’s blast at Shahid Rajaee port in Bandar Abbas, which also injured more than 1,000 people, was caused by “shortcomings, including noncompliance with safety precautions and negligence”.

Customs authorities have said imported cargo caught fire and exploded. The defence ministry has denied foreign reports that it was a shipment of a missile fuel chemical.