A man is in critical condition and a portion of Interstate 70 is closed in Warren County.Sgt. Al Nothum with the Highway Patrol said law enforcement received reports of a man running in and out of traffic and climbing on the hood of a moving semi-truck near the Flying J at State Highway B and I- 70 near the 188 mile marker.When a state trooper tried to make an arrest, Nothum said, the man ran into the westbound lane on I-70 and into the path of a semi-truck. Nothum said a medical helicopter was called to airlift him to a hospital.Westbound drivers are being diverted on the north service road from Warrenton to Jonesburg while the accident scene is being investigated.Nothum said the interstate may reopen by 7:30 or 8:30 p.m.