Two auto accidents on Maryland highways, in less than 15 minutes, around midnight yesterday, left four persons dead and four others seriously injured, state police said.

Shortly before midnight Saturday, police said, one member of a family from Lewisdale in Prince George's County died and three others were seriously injured when their car was struck head-on by a vehicle which crossed the median strip of the Beltway just west of Connecticut Avenue. A passenger in the family's car and the driver of the second car, a 60-year-old Philadelphia, were also killed, police said.

Police and fire officials said yesterday that Walter J. Rorie, driver of the car which crossed the median, apparently suffered a heart attack before the crash.

At 12:10 a.m., police said, a 30-year-old Alexandria man was killed and his wife was injured when their car crashed into an embankment on Rte. 5 near Clinton in Prince George's County.

Police say the first crash occured when the Rorie car crossed from the westbound side of 1-495 to the eastbound lanes. Rorie's auto slammed head-on into a car containing five persons, including four members of the William Reuille family.

Two other eastbound cars the ploughed into the wreck from behind, police said. One car struck the Reuille vehicle and the other, swerving to avoid the Reuille's car struck Rorie's.

Ross Marie Reuille, 12: passenger Lora Pearl Powell, 68, and Rorie were killed almost instantly, police said. William J. Reuille, 48, was taken to the shock trauma unit of University Hospital in Baltimore, and Mary Ann Reville, 47, and Frank Reville, 9, were admitted to Suburban Hospital.

William and Mary Ann Reville were listed in critical condition yesterday, and Frank Reuille was in serious condition. No one from the other two cars involved in the crash was injured, police said.

State Police said the Clinton crash was triggered when a car driven by an unidentified person swerved in front of the auto driven by Linda Meherg, 25, of 4804 Eaton Pl., Alexandria.

When Meherg turned trying to avoid a crash, police said, her car slipped off the road and crashed into an embankment. James Howard Meherg later died of internal injuries at Southern Maryland Hospital Center in Clinton, police said.

Linda Meherg was listed in satisfactory condition at Southern Maryland Hospital yesterday, police said.