Partial closure of a section of Kailua Road due to a large sinkhole will continue through at least Sunday morning when a contract crew can begin to fix the problem, a city official said Friday night.

The sinkhole, 20-foot long by 12-feet deep, is near the entrance to Kailua Town. It formed about 12:30 a.m. Friday morning near the corner of Hamakua Drive and Kailua Road.

What caused it had not been determined, although an 18-inch gravity sewer pipe appears to have broken in the process, said Markus Owens, spokesman for Honolulu’s Department of Environmental Services.

The plan calls for a contract crew to go in to fix the pipe and repair the sinkhole Sunday morning, he said.

The in-bound lane into Kailua was closed, and traffic was expected to be slow into Kailua Town.