Speed and drugs appeared to be factors in crash that left a 46-year-old Kailua man in critical condition Saturday in Moanalua, Honolulu police said.

The man was taken to a hospital in critical condition around 5:10 p.m. Saturday after crashing a box truck into a tree in a grassy median near North King Street and Paa Street.

Police said the incident began about a half-mile earlier when the man was seen driving the box truck erratically on Salt Lake Boulevard.

He ran a red light at the intersection of Salt Lake Boulevard and Puuloa Road, then headed northbound on Puuloa to King Street, police said.

While traveling at a high rate of speed, he took the exit to Paa Street, ran over a curb onto a grassy median and slammed into a tree.

Police said it was unknown if alcohol was also a factor in the crash.