KAILUA — An 8-year-old boy was in critical condition and a 7-year-old girl was in serious condition yesterday after the truck they were riding in crashed in a suspected case of negligent injury and driving under the influence.

The driver of the 1986 Toyota pickup truck, William Palakiko, 32, of an Ulupii Street address in Kailua, was arrested after being treated at Castle Medical Center.

Police said Palakiko was speeding and passing other vehicles on Kalaniana'ole Highway headed toward Kailua when he crashed at 10:15 p.m. Saturday night about a half-mile past the intersection with Kamehameha Highway, near Kapa'a Quarry Road.

The truck went out of control, struck a guardrail on the right shoulder of the road and rolled over twice, police said.

The children were riding in the cab of the truck and may have been ejected, police said.

They were being treated at The Queen's Medical Center yesterday.