MANILA — Black smoke billows behind lush palm groves. Tanks rumble past graceful minarets. Bullets rain on empty streets.

As the siege of the southern Philippine city of Marawi enters its fourth week, more than 200 people have been killed and much of the city lies in ruins. The strongest attempt yet by supporters of the Islamic State to seize and hold territory in Southeast Asia has turned into an urban street fight in what is now largely a ghost town.

Hastily closed businesses bear signs reading “looters will be shot.” Stray dogs scavenge for food on deserted streets. A light rain on Tuesday added to the feeling of despair.