Students displaced by a suspicious fire at a Hawaii elementary school are returning to classes on Monday after crews completed repairs and officials made temporary arrangements.

Kahului Elementary School was supposed to reopen Thursday following a Nov. 24 fire that damaged six classrooms and displaced 137 students. State Department of Education officials pushed the reopening to Monday, in part because of waterline damage, The Maui News reported.

The fire damaged waterlines running above ground, Hawaii Department of Education spokesman Derek Inoshita said. The lines had to be capped to avoid leaks before the full system could be restored.

Inoshita said the work has been completed, and the system restored.

Plans for portable classrooms still are in development and a timetable is pending, Inoshita said. The portables will need to be transported and situated before power and utilities are installed.

“The department’s facility branch is working on repairing and/or replacing damaged fixtures and buildings,” Inoshita said. “Any new construction will take time and allocated funds, which the department will handle once a full assessment is made.”

Police have opened an arson investigation. The fire caused an estimated $1.2 million damage to the structures and contents.

State Rep. Justin Woodson toured the damaged classroom wing. He noted he wasn’t an engineer but said he assumed the entire wing will need to be rebuilt.

Teachers have worked to accommodate the affected students in other classrooms since the fire, Inoshita said.