Upon reaching the vicinity of The Medical City, I found out that the small zippered compartment of my backpack was open. Probably because I walked and crossed Ortigas Ave. using the footbridge.
The footbridge is notorious for pickpockets—hooligans who would position themselves behind unknowing pedestrians wearing backpacks. In a flick of a finger with the featherlike touch, they could unzip bags and take wallets or mobile phones. Or your lunch if it looks very scrumptious.