Norway Building Collapses; 5 Missing

The search for survivors was initially interrupted by two later rock slides that hit the ruined structure, partly built into a steep hillside in Aalesund, about 220 miles northwest of Oslo.

Then a large propane tank buried in the debris caught fire and was at risk of exploding, forcing authorities to evacuate about 40 houses and apartments in the area and hampering rescue efforts.

Police said rescuers would not be able to enter the apartments until the propane burns out, which could take days.

The bottom floors of the apartments caved in just after 3:30 a.m., when the first slide slammed into the back wall.

"We first thought it was an earthquake," said Lars Aage Eldoey, who managed to escape with his wife from the top floor. When he got out on the balcony he realized what had happened.

"There were enormous rocks not just rocks half the hill had slid down into the bottom floors," he told state broadcaster NRK.

Smoke billowed from the twisted bottom floors of the collapsed building, with sagging balconies and a contorted glass entryway.

Police rescue leader Kjell Kvenseth said the fire spread to the upper floors, increasing the risk that the entire structure would fall down.

Fifteen people were taken to a hospital, two of them with moderate injuries, Aalesund police operations leader Magne Tjoennoey said.