KYIV, Feb 24 (Reuters) - Russian helicopters on Thursday attacked Gostomel, a military airport near the capital of Kyiv, and Ukraine downed three of them, Ukrainian officials said.

Ukrainian border officials said that the Russian military was trying to penetrate into Ukraine's Kyiv region and its Zhytomyr region on the Belarusian border and that Russia was using Grad rocket systems. (Reporting by Natalia Zinets; writing by Polina Devitt; editing by Tom Balmforth)