Police are searching for a man who allegedly shot and killed his stepfather – an off-duty Washington, D.C., police officer – at a Maryland home Monday.

Prince George’s County Police officers have obtained an arrest warrant for Antwan Rayvon James, 27, who they believe fatally shot Joseph Burrough Newell, 46, at a private residence in an Upper Marlboro, Md., gated community Monday evening.

Officials have identified Newell as an off-duty officer with the District of Columbia’s Metropolitan Police Department. A preliminary investigation suggests the slaying “stemmed from a dispute over yard work,” according to a police statement released Tuesday morning.

“We believe the shooting stems from a domestic situation,” said Officer Nicole Hubbard, a spokeswoman for county police.

Police officers responded to reports of a shooting in an upscale gated community, where Newell is believed to have lived, just after 8 p.m. Monday evening. Responding officers initially believed the shooter was hiding in the residence and erected a barricade shortly after 10 p.m.

But when police searched the home at 3 a.m., they determined that the gunman had fled and immediately dispatched officers in pursuit, Hubbard said.

“We believe the #UpperMarlboro domestic murder suspect is out of the immediate area,” authorities tweeted shortly after 3 a.m. “Active search underway.”

Newell was a 24-year veteran of the D.C. force, according to a police statement.

More than four years after a Prince George's County teen died after getting hit on her walk to school, her family was awarded tens of millions of dollars in a wrongful death suit, but the legal battle could be far from over.

The morning of Sept. 1, 2009, a Lincoln Continental hit 13-year-old Ashley Davis as she crossed Brinkley Road to get to her school bus stop. Some of her classmates watched in horror.

The car then struck a minivan and a 17-year-old boy.

“She was on her way,” her mother, Nycole Davis, said. “She was doing the right thing. She was going to school. She was a good girl. She didn’t deserve this.”

Ashley, a Crossland High School freshman, suffered catastrophic injuries and died two weeks later. Her parents sued the Prince George’s County School Board.

“The school board was negligent,” said John Costello, the lawyer for the family. “They had adopted a policy to provide for safe transportation. The policy was they were going to pick up Ashley on her own side of the street. They never did. They forced her to cross the street. She got killed crossing the street.”

“If she didn’t have to cross the street …  she’d be graduating this year,” her mother said. “She’d be going to prom this year.”

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At the end of the civil trial, a Prince George’s County jury awarded Ashley’s family a verdict of $90 million in damages plus medical expenses and funeral costs.

“I didn’t ask anyone to give me any money or anything like that,” her mother said. “I just want someone held responsible for what happened to my daughter.”

Prince George's County Public Schools emailed a statement to News4 saying, “No judgment has been entered in this case. It is still under litigation.”

Some cap a verdict or limit it in the neighborhood of $100,000 when there is a lawsuit against a municipality or school system, so this case could be far from over.

Reuters

Aaron Thomas, 41, known as the "East Coast Rapist."

The man referred to as the "East Coast Rapist" -- tied to a string of attacks along the Eastern Seaboard -- was indicted Tuesday in the county where he has said his reign of terror began.

Aaron Thomas, 41, was indicted by prosecutors in Prince George's County, Md., on six counts of first-degree rape and related charges, reported NBCWashington.com. He is accused of raping and kidnapping six women in the county between 1997 and 2001 and faces a total of 54 charges there, including first-degree sex-offense, kidnapping, theft, and false imprisonment, NBCWashington.com said.

Thomas is already behind bars in Virginia, serving five life sentences plus 80 years for a 2001 rape and abduction in Leesburg, Va., and a Halloween 2009 attack on three teenagers in Prince William County, Va.

"While we know that Mr. Thomas will spend the rest of his life in prison for his crimes, it is important that we prosecute him for the attacks he committed in our county, so these six victims can receive justice and closure from this terrible incident in their lives," said Prince George's County State’s Attorney Angela Alsobrooks in a statement on Tuesday.

Thomas is linked by DNA evidence to more than a dozen sexual assaults dating back to 1997 from the Washington area to Connecticut.

Thomas told The Washington Post that his first rape was in Prince George’s County, and described several assaults that predate the ones known to authorities by several years.

The earliest attack for which he has been charged is a February 1997 assault in Prince George's County, in which a woman was confronted by an assailant on a 10-speed bike, according to The Post. 

He wasn't captured until March 2011 after a massive manhunt following the 2009 Halloween attack.

In a tell-all interview with the Post on Nov. 10, 2012, from his Virginia jail cell, Thomas admitted he was the man known as the "East Coast Rapist," something he has also admitted to law enforcement. 

“I need help with this problem. It’s serious,” Thomas told The Post in 2012. “I don’t think I’m crazy, but something is wrong with me.”