Mexican authorities say at least four people died were when scaffolding collapsed at a cathedral under construction in the southern city of Tuxtepec.

The head of the Oaxaca state civil defense office says 19 people were injured, all of them apparently construction workers.

Felipe Reyna told the Televisa television network Friday that four workers are still missing. But he said it is unclear whether they had left of their own accord before or just after the collapse occurred late Thursday.

Searches continue at the La Barca Cathedral. But nobody else has been found in the massive jumble of wood left on the cathedral floor after the 80-foot (25-meter) tall scaffolding collapsed.