Moscow-backed separatists in southeastern Ukraine said they had taken down traffic signs spelling out the name of the besieged city of Mariupol in Ukrainian and English and replaced them with Russian ones."Updated road signs have been set up at the entrance to Mariupol," the transportation ministry of the self-proclaimed Donetsk People's Republic said in a statement on Thursday.The ministry released pictures of municipal workers in orange vests carrying away a road sign saying Mariupol in Ukrainian and English and installing a similar sign in Russian."Work to change road signs across the liberated territory will continue," the statement said, adding that similar work had been carried out in smaller settlements.Mariupol is one of the most battered cities in Ukraine and Russian forces have for weeks sought to wrest full control.On Thursday, Sergei Kiriyenko, first deputy chief of President Vladimir Putin's administration, visited the now-flattened city and other "liberated territories," a separatist leader said on social media.Locals wanted to see proof that "Russia has come back here forever," wrote Denis Pushilin, head of Ukraine's breakaway region of Donetsk.Seizing the strategically located port city would allow Moscow to create a land bridge between the separatist pro-Russian regions in eastern Ukraine and Crimea, which it annexed in 2014.Mariupol's sprawling Azovstal steel plant has become the last pocket of resistance, with Ukrainian troops staging a last stand there.Hundreds of civilians have been holed up for weeks under heavy bombardment, many taking shelter in the plant's Soviet-era underground tunnels.