An 8-month-old Laurel infant and two Bowie men were killed late Sunday on Rte. 197 in Bowie in a two-vehicle collision that also left five other persons injured, according to Prince George's County police.

The infant, Bonnie Ritter, was killed when she was thrown from a playpen to the front of the van in which she was riding with her parents and 3-year-old brother, police said. The parents, John and Connie Ritter, and their son, Jonathan, who live at 8802 Contee Rd., in Laurel, were in critical condition yesterday, authorities said.

James Warren Autry, 25, of Sulter's Lane, Bowie, and Michael Scott Finn, 17, of 3509 1malec La., in Bowie, also were killed in the crash, police said. They were riding in an automobile with Jo Anna Richter, 18, of 3904 Corbin Pl., Bowie, and Thomas John Rozanski, 19, of 4804 Reston La., Bowie, both of whom were in good condition yesterday, authorities said.

The Ritters were traveling north in their van on Rte. 197 near the Whitehall shopping center Sunday night when the southbound car, apparently traveling at a high rate of speed on a new, unopened portion of the road, suddenly turned sideways into the path of the van, police said.

Three people in the car were thrown out on impact, according to police.

Helen Rozanski said her son, Thomas, one of the survivors of the crash, told her yesterday. "We were riding along, all of a sudden there was a barrier in front us." Mrs. Rozanski said that Rte. 197 is being widened in that area, and part of the road is open while part is barricaded off from traffic.