This is the first full test of a warning system set up after the deadly 2004 tsunami in Asia.

The first sirens went off in the Banda Aceh region of Indonesia.

Volunteers are taking part in the simulation of a quake of more than magnitude 9.

That's similar to the one that triggered the massive tsunami five years ago off the Indonesian coast.

The province's deputy governor said the drill was a success.

[Mohamad Nazar, Deputy Governor, Banda Aceh, Indonesia]:
"The readiness of the Aceh people for a tsunami is getting better than in 2004, when many victims died because of the tsunami. In that time residents only knew that if an earthquake had happened they must get out of the buildings. Unlike in the Simeuleu Island where people already knew that if an earthquake was followed by a tsunami, they must seek higher ground."

These were the scenes in 2004 where 230, 000 people were killed in countries including Indonesia, Sri Lanka, Thailand and India.

The early warning system has been set up because of it at a cost of about 150 million U.S. dollars.

Eighteen nations took part in Wednesday's test of the system.

In Sri Lanka, a coordinating officer said that not everything went according to plan.

[M.G.A. Nandana, Disaster Management Agency, Sri Lanka]:
"We worked hard to make this a success. We educated the people of this village and we want to check how successful the flow of information was. Because the warning tower did not work we used loud speakers and sirens to inform the people of the tsunami. When we informed the people they gathered at the Buddhist temple which was a safe."

But experts have criticized the effectiveness of early alert systems. They particularly question those with a short time interval between the alarm and the hit, as would be the case in Indonesia which lies on fault lines.

Tsunami waves are extremely fast and can travel at a speed of more than 800 kph. When they get closer to the shore they slow and swell, and reach heights of 10 meters or more.