After the fatal crash on Feb. 27, and away from the scene, investigators positioned the cars as they were at impact: The silver Volt was driven by Michael Buarque de Macedo; Ogulcan Atakoglu was driving the blue BMW. (Montgomery County Police)

A Maryland man pleaded guilty Monday to vehicular manslaughter after speeding into a Chevrolet Volt carrying a family of four to a school play in February, killing three people, prosecutors said.

At about 7 p.m. on Feb. 27, 20-year-old Ogulcan Atakoglu of Potomac was driving a BMW M series 235i at 115 mph in a 45 mph zone at the intersection of River Road and Braeburn Parkway in Bethesda, the Montgomery County State’s Attorney’s Office said in a statement.

The BMW slammed the Volt broadside, court records showed, killing Michael Buarque de Macedo, 52; Alessandra M. Buarque de Macedo, 52; and their son Thomas Michael Buarque de Macedo, 18, who were on their way to a high school play and were five minutes from curtain time. Atakoglu hit the brakes as he tried to avoid the crash, but the BMW struck the Volt at about 75 mph.

Several horrified witnesses tried to help, including men who lifted a metal sign to try to pry open a door of the Volt and a doctor who went through a broken window to give aid. Helena Buarque de Macedo, the then-15-year-old daughter of Michael and Alessandra, was the only one in the Volt to survive.

“I did it! It’s all my fault!” Atakoglu was heard yelling at the scene.

Atakoglu pleaded guilty to three counts of vehicular manslaughter before Montgomery County Circuit Court Judge Mary Beth McCormick. Sentencing was set for Nov. 7, and Atakoglu was held without bond, according to prosecutors.

“Today’s guilty plea is the first step towards the long road of taking responsibility by Mr. Atakoglu,” Ramon Korionoff, public affairs director for the Montgomery County State’s Attorney’s Office, said in the statement. “While he and his family may feel the emotional sting of jail time, we believe the judge’s decision to. . . hold him pending sentencing is the just and fair action to take.”

David Felsen, an attorney for Atakoglu, said that the intersection where the accident occurred is dangerous, but his client had accepted responsibility for his part in the crash.

“This case is a tragedy all the way around,” Felsen said.

Each vehicular manslaughter count has a maximum penalty of 10 years, prosecutors said, and the guidelines in this case are three months to four years per count.