US-backed militias say they are battling Islamic State around Raqqa stadium, the jihadists' last foothold in their former Syrian capital, after seizing a nearby hospital.
The fall of Raqqa city, where Islamic State staged euphoric parades after its string of lightning victories in 2014, and from which it planned attacks abroad, is a potent symbol of the jihadist movement's collapsing fortunes.
It is now hemmed into a tiny bomb-cratered patch of the city around the stadium that is pounded from the air by a US-led coalition and encircled by Syrian Democratic Forces (SDF) fighters.
Islamic State has lost swathes of territory in Syria and Iraq this year, including its most prized possession, Mosul, and in Syria it has been forced back into a strip of the Euphrates valley and surrounding desert.
The SDF, an alliance of Kurdish and Arab militias, took the National Hospital in fierce fighting overnight and early on Tuesday, said spokesman Mostafa Bali in a statement.
"During these clashes, the National Hospital was liberated and cleared from the Daesh mercenaries, and 22 of these foreign mercenaries were killed there," said Bali, using the Arabic acronym for Islamic State.
An SDF field commander who gave his name as Ager Ozalp said three militiamen were killed by the mines that have become an Islamic State trademark in its urban battles.
He had heard estimates of about 100 Islamic State fighters remaining in their last besieged pocket, Ozalp said.
The stadium has become the last major position held by Islamic State after four months of battle in Raqqa and the departure of some of its fighters on Sunday, leaving only foreign jihadists to mount a last stand.