Residents in Sitka were evacuated amid heavy rains that triggered the landslides, Sitka city and borough spokeswoman Sara Peterson said.
She said two construction workers who were working on a home and the local fire marshal have not been heard from. There have been no further reports of injuries or calls for help, she said.
One home was destroyed and another was damaged, along with an office building, Peterson said.
She said rescue workers were proceeding with caution because the area was unstable and unsafe.
The city and borough's website said initially that four people were unaccounted for, but Peterson said officials had since confirmed that only three people are missing.
Further details were not immediately available.
Sitka is home to some 9,000 people and sits about 100 miles (60 km) south of the state capital, Juneau.