Cass County Sheriff Wm. C. Brueggemann advised that on Saturday, May 8 at 12:40 p.m. Cass County Deputies, along with Greenwood Fire & Rescue, Ashland Rescue, Cass County Paramedics, and Nebraska State Patrol responded to a two-vehicle injury accident at the intersection of State Hwy. 63 and Mynard Rd., just south of Interstate 80.  Peter Bartman (80, of Gretna) was eastbound on Mynard Rd. exiting the Antique Mall in a 2012 Ford F-150.  Bartman failed to yield at the intersection and continued into the intersection with State Hwy. 63 and into the path of a southbound 2007 Peterbilt being driven by Larry Langer (67, of Alvo).  Langer attempted to avoid a collision but did not have sufficient time to react.  Langer's truck struck Bartman's vehicle in the driver's door area.  Bartman's vehicle came to rest in the ditch southeast of the intersection.  Langer's semi jack knifed, coming to rest in the southeast corner of the intersection, blocking the northbound lane of Hwy. 63.  Peter Bartman was transported by Ashland Rescue to Bergan Mercy Medical Center in Omaha.  Judith Bartman (77, of Gretna) was flown by LifeNet to Bergan Mercy Medical Center in Omaha.  As of this time both are listed in critical condition with multiple broken ribs, possible broken pelvis, and internal injuries.  Langer was taken by private vehicle to St. Elizabeth's Hospital in Lincoln as a precaution.  Seatbelts were in use by Langer and Peter Bartman.  Alcohol and speed are not believed to be factors in the crash.  Crash is still under investigation.