MANILA - The Philippine capital shut down for an hour on Thursday morning for a government-initiated "shake drill" to test the nation's preparedness for a strong earthquake that experts say may kill at least 34,000 lives.
All over metropolitan Manila, private and government buildings were evacuated, as sirens blared, church bells rang, and emergency vehicles prowled the streets.
Posts on social media showed employees evacuating the main offices of the Philippine Stock Exchange in the Makati business district, the Supreme Court, House of Representatives, the central bank, and dozens of banks, shopping malls and condominiums.
Rescue and medical workers practised drills, extricating people "trapped" in homes and buildings and attending to volunteers posing as "injured" victims.
Firemen were deployed to put out simulated fire, drones flew around buildings to look for "survivors", and rescue helicopters hovered overhead.
Emergency messages were sent out to cellphones and thousands were taken to evacuation sites.
"Almost too real. What a rush," tweeted Ms Tarra Quismundo, a reporter from The Philippine Daily who was covering the justice ministry.
The metropolitan Manila-wide "shake drill" was meant to simulate a 7.2-magnitude earthquake from an active fault in the capital.
The country's earthquake-monitoring agency has warned that the West Valley Fault, a 100-km fault line that runs through six cities in metropolitan Manila, may soon deliver "The Big One".
The metropolis has a population of over 12 million.
Mr Renato Solidum, head of the Philippine Institute of Volcanology and Seismology, has warned that the West Valley Fault could shift any time based on its seismic history.
Four major earthquakes were believed to have taken place along this fault line over the last 1,400 years, with a recurrence interval of 400 to 500 years. The last major earthquake was recorded in 1658.
Experts estimate that a 7.2-magnitude earthquake triggered by the West Valley Fault that will last for just 30 seconds could kill over 34,000 people.
At least 1,600 people died when a 7.8-magnitude earthquake struck northern Philippines in 1990.
In a recent poll, the reinsurance company Swiss Re determined that Manila is the world's second riskiest city, after Tokyo, because of its vulnerabilities to natural disasters.
Metropolitan Manila Governor Francis Tolentino said Thursday morning's drill was meant to encourage a "culture of preparedness" among Filipinos.