Fire department officials yesterday were trying to determine the origin of a gas-like odor that sickened people near two Waipahu schools, sending seven people to a hospital.

Emergency personnel took five adults and two children under the age of 13 from Waipahu Intermediate School to a hospital in stable condition, said city Emergency Services Department spokesman Bryan Cheplic. The patients complained of nausea and dizziness, and some complained of lightheadedness, he said.

Capt. Terry Seelig, spokesman for the Honolulu Fire Department, said calls began coming in about 11:15 a.m., first from homes on Pupumomi Street, then from Honowai Elementary School and finally from Waipahu Intermediate School.

Those who called the fire department reported a smell similar to propane.

On Pupumomi Street, one person was treated and released, Cheplic said.

Seelig, who was in the area, said the smell was no longer noticeable as of 12:15 p.m.

"We believe it was probably a transient release of some sort," Seelig said.

Federal firefighters and representatives from The Gas Co. were in the area assisting in the effort to determine where the gas came from.