HANOI, Vietnam (AP) - A young Vietnamese pro-democracy blogger has broken the news of his own detention at Hanoi airport through Facebook, the medium that is energizing his country's activist movement and worrying its authoritarian rulers.

HANOI, Vietnam (AP) A young Vietnamese pro-democracy blogger has broken the news of his own detention at Hanoi airport through Facebook, the medium that is energizing his country's activist movement and worrying its authoritarian rulers.

In a video message posted by activists after his detention Wednesday, Nguyen Lan Thang says, "When you see this video it's certain that I have been arrested by security forces."

Security authorities were not available for comment Thursday.

Fellow activists who travelled to Hanoi airport to greet Thang say he was picked up there on his return from an overseas trip.

Thang recorded the message shortly before he flew home, and told friends to spread it if he is detained.