A modern Su-57 combat jet has been damaged in an attack by Ukrainian forces inside Russian territory almost 600 kilometres from the frontline, Ukraine’s HUR military intelligence directorate said on Sunday. At least one aircraft had been damaged in the attack on the Aktubinsk airbase in Astrakhan, the statement said. The Sukhoi Su-57 is a stealth jet that has been in service with the Russian air force since 2020. HUR published a satellite photo claiming to show the attack. A HUR spokesman said later that a second jet could also have been damaged in the attack, Ukrainian media reported. On Satu…