TEHRAN — The recent deadly explosion at Iran's Shahid Rajaee Port, one of the country's most vital trade hubs, has fueled public fury and growing demands for transparency. 

As the official death toll rose above 70, the Iranian government is facing fierce criticism over its handling of the crisis, with speculation that the incident was linked to a warehouse storing chemical materials allegedly used by the Islamic Revolutionary Guard Corps (IRGC) in its missile program.

"There is no such link," said Ehsan Moazzen, the deputy public relations chief of the IRGC's naval force, in an interview published by Iranian media on Tuesday. He argued that the port is a commerce hub with no place for military cargo. "We have no information about the cause, nor have we had any mission in the port."  

Several media reports and eyewitness accounts have been suggesting that the warehouse contained sodium perchlorate, a chemical used to produce solid fuel for Iranian missiles. The accounts were backed by earlier reports that an IRGC-owned cargo of the same material ordered from China had docked at the port last month.