A US counterterrorism expert explains the dynamics between Israel, Iran, Hezbollah and Hamas – and why Hezbollah presents new risks for the US and other places globally.
The war began when Hamas-led militant groups launched a surprise attack on Israel on 7 October, which involved a rocket barrage and a few thousand militants breaching the Gaza–Israel barrier, attacking Israeli civilian communities and military bases.
I think “began” is correct.
https://en.wikipedia.org/wiki/Israel–Hamas_war