Zelenskyy says he and his team work in the dark because if they switch the lights on, Russia could bomb them

• CBS' "60 Minutes" toured the Kyiv base of Ukrainian President Volodymyr Zelenskyy and his team.
• Zelenskyy said they have to work in the dark or Russia could target the place with bombs.

Ukrainian President Volodymyr Zelenskyy told CBS' "60 Minutes" that he and his team in Kyiv have to work in the dark to avoid becoming targets of Russian bombs.

CBS correspondent Scott Pelley interviewed Zelenskyy in his Kyiv command center on April 6. The interview aired on Sunday night.

CBS described the command center was a "fortress" full of troops and weapons. Video of the center showed blacked-out hallways and mattresses on the floor, with Pelley noting that some Ukrainian troops sleep there.

Zelenskyy told Pelley: "It has to be dark in here, you can't switch the lights on because a bomb could just fly in, during an airstrike," according to a translation of Zelenskyy's remarks shared by CBS.

Zelenskyy and his staff have been living there for 46 days as of Sunday, CBS reported.

When Pelley asked Zelenskyy if he was safe, Zelenskyy said: "Yeah, I'm fine. I feel pretty calm about it. Our guards are worried because there could be an airstrike. But when we get the air-raid evacuation signal we head downstairs."

Ukrainian citizens have been escaping to underground bunkers, some of which were fashioned from subway stations and schools, to avoid airstrikes since the beginning of the war.

Pelley also asked him: "Mr. President, what has it been like working under these conditions?"

Zelenskyy replied in English: "We found a way to work. We don't have another way."

Western intelligence assessments said that Russia initially expected to seize control of Ukraine in days. Instead, Russia has been fighting there for more than a month, and Ukrainian forces have retaken control of some areas.

Russian troops have withdrawn from Kyiv, though Zelenskyy and Ukrainian officials said they expect Russia to try to take the capital again, and that shelling was still continuing there.

Zelenskyy has stayed in Ukraine. CBS noted that Russia expected Zelenskyy to flee, which would help secure a quick victory. Zelenskyy has also refused the US' offer to evacuate.