Speed appears to be a factor in a crash on the H-1 Freeway in Halawa that left a 36-year-old motorcyclist in critical condition early today, police said.

The crash occurred about 12:30 a.m., and police closed all Ewa-bound lanes of the H-1 Freeway to investigate.

Police said a Honolulu man speeding on a motorcycle rear-ended a passenger van. The motorcyclist, who was wearing a helmet, was thrown from the motorcycle and was taken to a hospital in critical condition.

The driver of the van was not hurt. Police reopened all of the Ewa-bound lanes about 4 a.m.