Is Bashar Assad insane? I can't imagine a Syrian mortar crew taking it upon themselves to fire a round at an Israeli military station on the Golan Heights.

But that is what happened for the second straight day. And Israel didn't fire a "warning shot" this time.

Reuters:

Israel's army fired tank shells into Syria on Monday and scored "direct hits" in response to a Syrian mortar shell that struck the Israeli-occupied Golan Heights, the Israeli military said in a statement.

It was the second time in as many days that Israel had fired across the disengagement line drawn at the end of a war in 1973, underscoring international fears that Syria's civil war could ignite a broader regional conflict.

Israeli military sources said Syrian mobile artillery was directly hit in the incident. There was no immediate word on whether it had been in the hands of Syrian army forces or the rebels they are battling.

On Sunday the military said it had a fired a guided missile into Syria in a potent "warning shot" after errant mortar fire had fallen on land that Israel seized in a 1967 war.

On Monday Israel upped the ante and carried through with a threat to target directly anyone firing across the lines.

"A short while ago, a mortar shell hit an open area in the vicinity of an (Israeli Defense Forces) post in the central Golan Heights, as part of the internal conflict inside Syria, causing no damage or injuries," the military statement said.

"In response, IDF soldiers fired tank shells towards the source of the fire, confirming direct hits. The IDF has filed a complaint with the U.N. forces operating in the area, stating that fire emanating from Syria into Israel will not be tolerated and shall be responded to with severity."

Assad can't believe that starting a war with Israel would save him. But perhaps he is that desperate. I doubt whether the rebels would take up arms alongside Syrian troops to fight their mortal enemy. More likely, they would take advantage of the situation to capture more territory.

Fallout from the Syrian civil war is becoming very dangerous.