OLD ORCHARD BEACH — Fire officials don’t know what caused the early morning blaze at the Galaxy nightclub, or where in the two-story building it might have started, Old Orchard Beach Fire Chief John Glass just told reporters gathered at the scene.

Four ladder trucks continued to douse the building at 11 a.m., but it appeared that nearby buildings were safe. A T-shirt shop is attached to the building to the east, and Ernesto’s restaurant is about 10 feet away from the Galaxy to the west.

Glass said he expects firefighters to be putting out hot spots during the day. There is an official from the state Fire Marshal’s Office at the scene, but it’s unlikely he will be able to get inside the building for several hours, Glass said.

“As far as we know, there was no one in the building before the fire,” Glass said. The Galaxy was closed at the time. Fire officials did evacuate a small number of people who were in nearby buildings along East Grand Avenue, but those buildings have since been reopened.

The fire broke out between 8:15 and 8:30, and a man who works within sight of the building said he first saw smoke coming out of the ground floor at about that time.

A strong onshore breeze created very smoky conditions for blocks. The plume could be seen for miles and hundreds of people have gathered to watch the scene, many taking pictures and video. Other beachgoers, in swimsuits and hauling beach provisions were walking by with barely a glance.

At least two firefighters are being evaluated for overheating, but no one has been transported to the hospital and there are no other injuries, Glass said.

The Galaxy had a fire inspection within the last three months, the chief said. The only concern from that inspection was that the second floor was being used for storiage and the owner was in the process of removing wood and other materials stored there.

Glass said that quick response and cooperation from Scarborough, Saco, Biddeford and Old Orchard Beach fire departmenst allowed crews to knock down the fire quickly, preventing it from spreading in the densely built area.