A Pinellas County deputy was seriously injured after crashing into a propane tanker truck early Tuesday morning.The Florida Highway Patrol said the Amerigas Propane tanker truck was traveling in reverse across the eastbound and westbound lanes of Hudson Avenue around 5:23 a.m. Its driver, a 60-year-old Spring Hill man, was attempting to get into a private driveway at 15222 Hudson Avenue.A marked Pinellas County Sheriff's Office Chevy Tahoe heading east on Hudson Avenue then collided with the tanker truck west of Hays Road and traveled underneath its trailer.The 32-year-old on-duty deputy was seriously injured and taken to a local hospital. The tanker truck's driver was uninjured.FHP said the deputy remains hospitalized and asked motorists to avoid the area as fire crews burn off the propane remaining in the tanker.