BEIRUT (AP) — A video posted online Saturday purportedly shows Islamic State fighters killing some 25 Syrian government soldiers in the historic town of Palmyra in central Syria. The capture of Palmyra has raised concern that the militants might try to destroy one of the Mideast's most spectacular archaeological sites — a well-preserved, Roman-era city on the town's edge — as they have destroyed other pre-Islamic ancient monuments elsewhere in Syria and Iraq.