KYIV, Ukraine (AP) — Russia fired more than 100 drones at civilian areas of Ukraine overnight, authorities said Monday, as the Kremlin dismissed its transportation chief after a weekend of travel chaos when airports grounded hundreds of flights during the busy vacation season due to the threat of attacks from Kyiv.

Russia and Ukraine have exchanged hundreds of drone strikes, causing several deaths and significant disruptions

Ukraine said it struck a Russian air base on Saturday, while Russia continued to attack Ukraine with hundreds of drones overnight as part of a stepped-up bombing campaign that has dashed hopes for a breakthrough in efforts to end the more than 3-year-old war.

Ukraine's top military commander Oleksandr Syrskyi warned on Saturday of a possible new Russian offensive in the Kharkiv region, a part of northeastern Ukraine which has seen heavy fighting since Russia invaded in 2022.