A 27-year-old woman turned herself in to police on Wednesday and was charged with shooting her boyfriend inside a moving car, which then crashed in Germantown on Tuesday, Homicide Capt. James Clark said.

Terrell Bruce, 33, and Martina Wescott were arguing Tuesday afternoon inside the Ford Expedition on Tuesday afternoon.  They were on the 500 block of Walnut Lane when Wescott shot Bruce in the head, police said.

A semi-automatic handgun was found in the leaves near the Walnut Street Bridge by police investigating Tuesday's shooting and automobile crash. (DAVID SWANSON / Staff Photographer)

The shooting caused an accident with another vehicle around 12:30 p.m., and the Expedition overturned, police said.

Police arrived within minutes of the accident and found Bruce, a real estate agent from the 900 block of E. Hortter Street, unresponsive inside the car, according to police.  Police have not indicated who was driving the Expedition at the time of the shooting.

Medics determined that Bruce had been shot once in the right temple and pronounced him dead at 12:35 p.m., police said.

 Investigators gather around a crash Tuesday in Germantown, in which a man was found shot dead inside an SUV. (Joseph Kaczmarek / For the Inquirer and Daily News)

Bruce graduated from La Salle University in 2008, said his twin brother Brandon Bruce, who was on vacation in Europe when he learned about Terrell's death.

"Terrell was a man of many talents. He knew he wanted to make a change in people's lives," said Brandon, who works as a lawyer with the U.S. Food and Drug Administration in Maryland.

Brandon said his brother wanted to stay in Philadelphia and help people to gain home ownership and financial independence.

Wescott, a graduate of Central High School and the University of Pennsylvania, turned herself in to police Wednesday, and was charged Wednesday afternoon.

According to a fundraising campaign she started on Fundly, Wescott was slated to leave Wednesday for a European vacation.

Brandon Bruce said he did not know his brother's girlfriend.  He said more attention should be paid to gun violence and stricter gun regulations.

The fraternal twins were born in Philadelphia — Brandon seven minutes ahead of Terrell — and grew up in an East Mount Airy house that Terrell later bought and lived in.

Their mother died when they were 13 years old. In 2009, their younger brother Nathaniel Kirkland drowned in Guatemala during a service mission for Dickinson College, Brandon said in a phone interview Wednesday night from Vienna, Austria.

Terrell established a scholarship foundation to honor Nathaniel.

A GoFundMe page has been set up by Bruce's family to help cover funeral expenses.