Four people were wounded and a transport infrastructure facility was damaged in a series of drone strikes on Ukraine's northeastern city of Kharkiv early on May 21, regional officials reported. “Regarding the morning attack, the target was a transport infrastructure facility,” Kharkiv Mayor Ihor Terekhov wrote on Telegram. Governor Oleh Synyehubov also said on Telegram that an infrastructure facility had been damaged, and added that debris from fallen drones damaged several private houses in Ukraine's second-largest city. Earlier a general air-raid alert was declared for the whole territory of Ukraine. To read the original story by RFE/RL's Ukrainian Service, click here.