It came down between this kindergarten, in eastern suburb of Brovary and a residential block.
Three children were among the dead, President Volodymyr Zelenskiy said, calling the crash a "terrible tragedy".
"The pain is unspeakable," he said in a statement.
Ukrainian officials said the cause wasn't immediately clear. They made no reference to any Russian attack in the area at the time.
National police chief Ihor Klymenko confirmed that Interior Minister Denys Monastyrskyi was killed alongside his first deputy, Yevheniy Yenin, and other ministry officials on board.
Monastyrskyi was the most senior Ukrainian official to die since the war began.
The French-made Super Puma helicopter was operated by the state emergency service.
At least six people were killed on the ground, officials said, including the children.
According to the regional governor, at least 29 were injured, 15 of them children.
Air force spokesperson Yuriy Ihnat said it could take several weeks at least to investigate the disaster.
"Unfortunately, the sky does not forgive mistakes, he said.
