The lower portion of St. Louis Drive will remain closed for at least another hour until road crews can remove a 5-foot tall boulder that was dislodged by a single-vehicle crash this morning, police said.

Police blocked off a portion of the road to traffic and TheBus was rerouted until the boulder could be removed.

The boulder was dislodged by a truck coming down St. Louis Drive faster than the posted speed, police said.

The truck struck the rock, which landed in the mauka lane. No one was injured in the 8:45 a.m. crash. The truck flipped over on its passenger side, police said.