Hacking thru the radar

Last week's Israeli Air Force strike in Syria may have used advanced electronic deception transmissions to confuse the up-to-date Russian made Syrian anti aircraft defenses. Systems are known that can invade air defense communications systems, cause them to transmit their radar views back to the attackers, and even issue false orders to cause sensors to look away from attackers, designate radar tracks as friendly, or insert false tracks.
Seeing the enemy radar's view is extremely valuable to attackers, it shows the blind spots in enemy radar coverage and lets the strike aircraft know when they are flying low enough to avoid detection. Radars contain various circuits or software to filter out clutter. It may be possible to crank those filter setting up so high that the attacker's radar tracks are filtered out. Or have the radar label the attackers tracks as friendly airliners. Or simply fill the system with so many false targets that the real attackers are lost in the crowd.
Hard information is a little scarce, Aviation Week is reduced to quoting Arab newspaper articles. "Russian experts are studying why the two state-of-the-art Russian-built radar systems in Syria did not detect the Israeli jets entering Syrian territory" according to the Kuwaiti newspaper Al Watan. It goes on to say "Iran reportedly has asked the same question, since it is buying the same system and might have paid for the Syrian acquisitions".
Syria has recently acquired the Tor-M1 (SA-15 Gauntlet) a mobile system with guidance radar, missile launchers and missile reloads all mounted on tracked vehicles. Tor-1 costs $29 million per system.
The actual site of the attack, and it's contents are still a matter of dispute. Some reports place the attack at Tall Al-Abyad up in the Turkish border, others place it at Day az-Zawr out near the Iraqi border. The site may have contained nuclear material on route from North Korea to Iran, or it may have been a more run-of-the-mill storage for conventional munitions bound for Iraq, or Hezballah, or Iran. News reports are conflicting.
Naturally successful use of secret electronic countermeasures tells the enemy that his system is vulnerable and that codes must be changed and fixes invented. The Syrian target must have been pretty high value for the Israelis to disclose the effectiveness of their electronic countermeasures.