"They're real stable," said Bryan Cheplic, spokesman for the Honolulu Emergency Services Deparmtent. "The symptoms include minor stomach aches, watery eyes, being nauseated, dizziness and shortness of breath."

The gas has not been identified, he said.

Five of the patients were preschoolers aged 3- to 5-years-old. The rest were 10- and 12-year-old children, Cheplic said.

Authorities said fumes from a car fire filtered through the playground of Our Lady of Perpetual Help Catholic preschool on Ma Ke Kula Street in 'Ewa.

Hospital spokeswoman Cheryl Tamura said all 23 were treated for inhalation of gas. None were seriously injured. Some children were already being taken home by their parents less than an hour after their arrival at the hospital, she said, and no one was expected to require overnight hospitalization.

The fire broke out in a back street behind the school playground.

School officials moved students into the church, and several students began complaining dizzines and burning eyes.

Five fire companies, including a Hazmat unit, were sent to the school church, said Capt. Kenison Tejada, fire department spokesman.

Tejada said about 20 children were initially affected.

Firefighters at first responded to a car fire at 12:41 p.m. and other companies were called after a suspected gas leak was reported at 1:04 p.m.