And pretty much everything else in the immediate vicinity, including a pretty major Syrian military installation.
Consider the implications.
By the size of the secondary explosion, there must have been a sizable cache of Iranian missiles and warheads staged there for use by terrorists.
This cache represents a huge investment in time and assets by Iran to build the missiles and launch systems.
The facility is near an airport, so the Iranian's also must have spent a huge amount of assets airlifting them into Syria, along with lots of other ordnance.
According to reports, Iran had completed what must have been many months of covert deliveries of missiles and were in the process of transferring them to Hezbollah Terrorists.
This transfer no doubt meant the there were many high level Syrian, Iranian, Hezbollah, North Korean and possibly Pakistani officials, high level Military personnel, highly trained technicians from the above countries , and the terrorist crews training to operate the missile batteries all on site.
In effect, the Israelis allowed Iran and Syria to transport and stage a huge quantity of ordnance, munitions intended to launch a war of aggression and terror against Israel, into one of the Crown Jewels of Syrias Military-Industrial Complex and effectively used that ordnance to completely destroy that facility along with a lot of irreplaceable, high value and high-level personnel
This is a huge loss Syria, Iran and Hezbollah and poetic justice of the highest order
5-10-5! (from a time back when the world still understood right from wrong)