Countries are evacuating their nationals from Israel and Iran by air, land and sea as conflict rages between the bitter Middle East rivals.

The Israeli military told people in two central Iranian cities, Arak and Khondab, to evacuate immediately ahead of planned strikes. Arak is home to a [heavy-water reactor, under construction,](

Israel and Iran have been enemies for decades — but this is their most sustained direct fighting ever. Here’s how a shadow war erupted into an overt conflict.