The Times interviewed Russian soldiers who said they face a brutal fight to dislodge determined Ukrainian forces from a sliver of Russian land. Trapped civilians fear catastrophe.

The leader of Azerbaijan criticized the Russian response to the crash of a passenger jet that Azerbaijani officials said had most likely been hit by Russian air defenses.

President Vladimir V. Putin of Russia told the Azerbaijani leader, Ilham Aliyev, in a phone call, “that the tragic incident took place in Russian airspace.”