One hundred and fifty firefighters from around Solano County and CalFire are on the scene battling a six-alarm fire west of Vacaville near the Lagoon Valley Regional Park this morning. Flames were first spotted around 1:30 a.m. in the area of Pleasant Valley and Cherry Glen Roads, near I-80. Four hundred acres had burned by 5 a.m., and 50 percent of the fire was contained by 6:45 a.m. Full containment is expected later today. No one has been injured, and evacuations are not expected. The Cherry Glen Road off-ramp of I-80 has been closed indefinitely to accommodate responding fire crews and equipment.