BEIRUT — Syrian government forces battling the Islamic State group re-entered Palmyra on Thursday in their quest to again take the historic town they had lost to the militants in December, state media reported.

The Kremlin’s spokesman said President Vladimir Putin was informed by his defense minister that Syrian troops had gained control of Palmyra, with support from Russian warplanes. However, there was no immediate confirmation of Palmyra’s seizure from the Syrian military and the Russian reports did not provide more details.

The SANA news agency reported earlier that government troops had entered the town’s archaeological site, a UNESCO World Heritage Site, around mid-day, then the town itself, as IS defenses crumbled and militants fled the area.

It said army units were engaged in “precise tactical operations” and chasing remnants of IS fighters holed up inside the ancient town.