The first casualties after the adoption of Resolution 181(II) were passengers on a Jewish bus near Kfar Sirkin on 30 November, after an eight-man gang from Jaffa ambushed the bus killing five and wounding others.
But you can always go back a little further with this stuff, it’s been going back and forth seemingly forever:
This was stated to be a retaliation for the Shubaki family assassination, the killing of five Palestinian Arabs by Lehi near Herzliya, ten days’ prior to the incident.
In any case, a more accurate assessment of the civil war before the birth of Israel is that it was a bloody tit for tat:
From January onward, operations became increasingly militarized. In all the mixed zones where both communities lived, particularly Jerusalem and Haifa, increasingly violent attacks, riots, reprisals and counter-reprisals followed each other. Isolated shootings evolved into all-out battles. Attacks against traffic, for instance, turned into ambushes as one bloody attack led to another.
The UN proposed 2 separate nations, this satisfied the Palestinian Jews, but not the Palestinian Arabs. Palestinian Arabs fought a civil war against the Jewish Palestinians, they lost. Israel was formed. Arab nations got together and fought a war against Israel, and they lost again. Then again in the War of Attrition. And again in the 1st Yom Kippur War. Once more in the Lebanon War. It doesn’t look like Palestinians have the upper hand in this Yom Kippur War, either.
Why should the party who keeps starting wars and keeps losing them get complete control of the region?
A one-state solution might be the ideal outcome, but there’s no way of that happening with either side taking over. It would have to be the dissolution of both state governments alongside the cooperative formation of a new government. With the back and forth conflict that’s always been happening, there’s just no way this can happen right now. The two sides need to separate themselves, stop fighting, then maybe some time a long way in the future they can come together.