“Mounting pressure”, much like “condemnation”, means absolutely nothing. Isreal will continue to whatever the hell they want and with immunity because western nations are so desperate for a middle eastern ally.
There were tunnels. The aid delivery contained smuggled weaponry. Hamas fighters were seen nearby. They ignored warnings not to proceed. Someone threw a stone.
Pick one or multiple at random. There won’t be any repercussions anyway. Oh boy, I wonder how Gazans grew so resentful.