Freetown, Sierra Leone (CNN)Dozens of construction workers are feared missing in Sierra Leone after a three-story building collapsed, officials told CNN on Thursday.
Ten people have been rescued from the building, which was still under construction when it came down Wednesday in Bo, the country's second largest city, local police said.
Some survivors sustained critical injuries and may be transferred to a better-equipped hospital in the capital, Freetown, some 250 kilometers (155 miles) away, Bo District medical officer, Dr. Roland Marsh, said.
More than 70 construction workers reported for work at the building, said regional police commander Kapri Saidu Kamara, and rescuers are searching for those feared trapped under the building.
One worker, Abu Sesay, narrowly escaped, then watched as the unfinished building collapsed with some of his coworkers inside it, he said.
"We started working. Some were up the building, and others were down, including some (construction materials and food vendors). I heard the heavy sound and didn't know how I managed to survive this," Sesay said.
The Sierra Leone Roads Authority had tried to stop the construction work, citing its proximity to a major road, agency engineer Francis Bendu said.
"The construction work is on the right of way," Bendu said. "As always, we try to stop people from building in such area to save the government from paying unnecessary compensation if they want to expand on the road."