Three people died on Southern Maryland roads in two separate vehicle crashes Tuesday and Wednesday, authorities said.

Niko Stergiou, 21, and Jacob Stergiou, 16, both of North Beach, were killed just after 7 p.m. Wednesday after the Chevrolet Cavalier in which they were traveling eastward on Plum Point Road in Huntingtown crossed the center line and struck a Chevrolet Suburban, according to the Calvert County Sheriff's Office.

The Suburban then struck a guardrail and caught fire. Citizens helped the occupants of the Suburban to safety as paramedics and police arrived, according to the sheriff's office.

Niko Stergiou, who was driving the Cavalier, was pronounced dead at Calvert Memorial Hospital. Jacob, who was sitting in the rear passenger seat, was ejected from the vehicle. He was flown to Prince George's Hospital Center, where he later died. Jacob was a freshman at Northern High School in North Beach, according to school officials.

Another passenger in the Cavalier, Todd Williams, 19, of Owings, was also taken to Prince George's Hospital Center. His condition was not immediately known.

The driver of the Suburban, Tina Hassler, and a 3-year-old passenger were rushed to Washington Hospital Center. A 17-year-old passenger in the Suburban was transported to Calvert Memorial Hospital. Their conditions were unknown, according to the sheriff's office. The crash is being investigated by the Calvert County Sheriff's Office.

In a separate accident, at about 5:40 a.m. Tuesday, William E. Yuhasz III, 20, of Indian Head, was killed when the vehicle he was driving crossed the center line on Pope's Creek Road in Newburg and struck an embankment.

Speed is believed to be a factor in the crash, according to the Charles County Sheriff's Office. The investigation is ongoing.