The President of the Philippines, Gloria Arroyo, has declared a state of emergency after the army said it had foiled a coup plot.
Three commanders of elite units have been dismissed and are under investigation.
Rumours of a coup plot have been circulating this week as the country marks the 20th anniversary of a revolt that ousted President Ferdinand Marcos.
Security forces say the coup was set to start during anti-government protests later today.
The police have withdrawn permits for all planned demonstrations.
Several commanders of elite units have been accused over the plot.
