Two people were critically injured this morning in a fire at a housing development in Potrero Hill. 

The San Francisco Fire Department (SFFD) first reported the one-alarm fire on the 1100 block of Connecticut Street at 8:25 a.m. The blaze ignited on the second floor of the three-story building, which the Chronicle reports is currently partially under construction.

Construction workers helped residents exit the building, and were able to rescue one critically injured victim from the building's first floor. SFFD later rescued a second critically injured person from the second floor. Both were transported to the hospital. 

At 8:43 a.m., SFFD reported that the fire was under control. The agency also said that a family of five has been displaced from the building in the wake of the fire.

The blaze remains under investigation. We'll continue to provide further updates on the condition of the injured victims as they become available.