Syria has admitted some installations in its territory were hit by Israeli air strikes in late January, but facts about the "stealth attack" remain clouded by rumour.
Some sources claim an Israeli air force attack was made against a Syrian convoy transporting Russian-made SA-17 surface-to-air missiles intended to be passed to Hezbollah militants in Lebanon.
The Syrian authorities, by contrast, have officially announced the target was a "scientific research centre", with Syrian state television saying two people had been killed and five wounded in the attack.
Israeli air force
The air strikes are reported to have involved Israel's F-16 combat aircraft
Other sources say the raid had a secondary purpose: to test the capability of Syria's anti-aircraft system to detect fighters entering its airspace.
The mystery surrounding the attack continues to generate other theories. On 31 January, Iraqi newspaper Azzaman quoted Western diplomatic sources as saying the alleged Israeli attack caused heavy casualties to Iranian Revolutionary Guard personnel at the Syrian facility. Its sources also indicate the strike took place more than 48h before it was reported on 30 January, after being leaked by Israel.
One source, interviewed by Azzaman in London, said the convoy strike rumour was probably spread to divert attention from the main objective of the operation, which used Lockheed Martin F-16s to release at least eight guided weapons at the Syrian research centre. The same source claims the heavily fortified base contains Russian scientists and at least 3,000 members of the Iranian Revolutionary Guard.
Despite uncertainty over the true nature of the air strikes, it is clear the aircraft involved were able to fly into Syrian territory without being detected by the country's network of Russian-supplied early warning systems.
The Israeli military declined to comment.