SEOUL — Trash from at least one North Korean balloon fell on South Korea's presidential compound on Wednesday, raising worries about the security of key South Korean facilities from the North's provocations.

The garbage that fell at the compound in central Seoul contained no dangerous material and no one was hurt, South Korea's presidential security service said. While Pyongyang likely lacks sophisticated technology to drop balloons on specific targets, some experts say Seoul should shoot down incoming North Korean balloons to protect key facilities despite the prospect of increased tensions or damage on the ground, as they might contain dangerous substances in future campaigns.