An explosion took place at an Iranian gas storage facility in an area which houses a sensitive military site near the capital, Tehran, according to a defence ministry spokesperson.

Iran's defence ministry spokesperson Davoud Abdi told state TV on Friday the blast happened at a gas storage facility in a "public area" of Parchin.

He added that firefighters put out the fire. Investigations were under way to determine the cause of the incident. No casualties were reported, he added.

The tank blew up around midnight on Thursday, with Fars news agency saying "a number of social media users reported seeing an orange light" in the east of the Iranian capital.

Fars said that the flash of light was caused by "an industrial gas tank explosion" near a facility belonging to the defence ministry.

Mehr news agency said a "terrible sound" was heard.

"The cause of this sound and light is not yet known, but it was clearly heard in Pardis, in Boumhen and surrounding areas" of the Iranian capital, Mehr reported.

Al Jazeera could not immediately verify purported videos of the explosion that went viral on Twitter.

Al Jazeera