The United Nations¡¯ nuclear watchdog has called for a no-fire zone around an embattled Ukrainian nuclear generator, but ¡ª like the plant itself ¡ª the agency was quickly caught up in the war between Russia and Ukraine.

In a highly anticipated report released Tuesday, nuclear inspectors who had to wend their way through the battlefield to reach the plant said they were ¡°gravely concerned¡± about conditions there.

¡°We are playing with fire, and something very very catastrophic could take place,¡± said Rafael Mariano Grossi, the U.N. official who led the inspectors, in an address to the Security Council on Tuesday afternoon.