In a tweet on Friday Intelli Times, an online Israeli intelligence blog, said they could confirm from satellite images that the blast in Tehran on Thursday occurred at a facility at Khojir in the southeast of the capital.
Images posted by Intelli Times on Twitter show a building, probably a gas power unit, in the northeastern corner of Hemmat Missile Industries Factory of Khojir, responsible for developing ballistic missiles.
The facilities also assist the Hezbollah of Lebanon with the technology for precision missile projects in Syria and Lebanon, another tweet by Intelli Times on June 26 said and claimed that the explosion has apparently paralyzed the complex's gas facility.
However, another Twitter user has pointed out under the post that in the image provided with the tweet, the roof of the building appears intact despite the explosion.
The massive bright orange light from the blast was seen by residents of the capital and reported on social media almost immediately. The flash, as seen in videos, was followed by a large plume of smoke but the blast sound was not heard too strongly according to those who reported seeing the light flash.
Iran's Defense Ministry on Friday said the explosion had happened at a gas-storage facility in the "public area" of Parchin, a military complex about 30 km (19 miles) southeast of Tehran and to the south of Khojir.
Observers have linked the explosion to Revolutionary Guard facilities in the area that might be either nuclear research or missile assembly sites.
The Revolutionary Guard has massive underground tunnels in Khojir area for assembling and storing missiles which it unveiled in October 2019. Iran is also suspected of unreported nuclear activities at nearby Parchin and has barred IAEA access to the site.
Footage of the explosion site aired by the state-run television showed a small pipe that had burst open and exploded and blackened gas cylinders.