"You may have a very sophisticated system but the real test is how that ultimately leads to timely evacuation and actionable information, " Vatsa said.

CNN: Asian tsunami warning system: A last-mile challenge

Krishna Vatsa, the UNDP's disaster-reduction adviser in South Asia, said the warning system would help reduce the number of deaths from a similar situation in the future.

CNN: Asian tsunami warning system: A last-mile challenge

"We still have a long way to go, " Vatsa said.

CNN: Asian tsunami warning system: A last-mile challenge