AUBURN — Two days after falling through a skylight at the Auburn Mall, a Biddeford man remained in critical condition at a Lewiston hospital, an official said.

A Central Maine Medical Center spokesman said Friday that 43-year-old George Beam was still being treated for injuries suffered in the Wednesday afternoon incident.

Investigators said Beam was on the roof at about 1:30 p.m. Wednesday when he fell through a Plexiglas skylight and landed on a concrete floor more than 20 feet below.

He had been working on a heating and cooling system at the time, police said. According to an Auburn Fire Department official, Beam likely mistook the skylight for a snowdrift and stepped on it.

The U.S. Department of Labor’s Occupational Safety and Health Administration is investigating the accident. An official there said the probe could take up to two weeks.