MAKASSAR, Indonesia — An early warning system that might have prevented some deaths in the tsunami that hit an Indonesian island Friday has been stalled in the testing phase for years.

The high-tech system of seafloor sensors, data-laden sound waves and fiber-optic cable was meant to replace a system set up after an earthquake and tsunami killed nearly 250,000 people in the region in 2004.

But interagency wrangling and delays in getting just $69,000 to complete the project mean the system hasn’t moved beyond a prototype developed with $3 million from the U.S. National Science Foundation.

It is too late for central Sulawesi, where walls of water up to 20 feet high and a magnitude 7.5 earthquake killed at least 832 people in the cities of Palu and Donggala, tragically highlighting the weaknesses of the existing warning system and low public awareness about how to respond to warnings.

“To me this is a tragedy for science, even more so a tragedy for the Indonesian people as the residents of Sulawesi are discovering right now,” said Louise Comfort, a University of Pittsburgh expert in disaster management who has led the U.S. side of the project, which also involves engineers from the Woods Hole Oceanographic Institute and Indonesian scientists and disaster experts.

“It’s a heartbreak to watch when there is a well-designed sensor network that could provide critical information,” she said.

After a 2004 tsunami killed 230,000 people in a dozen countries, more than half of them in the Indonesian province of Aceh, a concerted international effort was launched to improve tsunami warning capabilities, particularly in the Indian Ocean and for Indonesia, one of world’s most earthquake and tsunami-prone countries.

Part of that drive, using funding from Germany and elsewhere, included deploying a network of 22 buoys connected to seafloor sensors to transmit advance warnings.

A sizeable earthquake off Sumatra island in 2016 that caused panic in the coastal city of Padang revealed that none of the buoys costing hundreds of thousands of dollars each were working. They’d been disabled by vandalism or theft or just stopped working because of a lack of funds for maintenance.