July 5 (Reuters) - Russian air defences shot down four Ukrainian drones headed for Moscow on Saturday, the city's mayor said, while one of the capital's main airports temporarily halted outgoing flights. Mayor Sergei Sobyanin said emergency services were working at the sites of the downed drones, but gave no information on potential damage.

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

Russia fired 322 drones and decoys into Ukraine overnight into Saturday, Ukraine’s air force said. Of these, 157 were shot down and 135 were lost, likely having been electronically jammed.