Almost a year after two teenage girls were found dead - allegedly executed by their father - in the back seat of a taxicab in Texas, the FBI is saying for the first time that the case may have been an "honor killing."

Sarah Said, 17, and her sister Amina, 18, were killed on New Year's Day, but for nine months authorities deflected questions about whether their father - the prime suspect and the subject of a nationwide manhunt - may have targeted them because of a perceived slight upon his honor.

The girls' great-aunt, Gail Gartrell, says the girls' Egyptian-born father killed them both because he felt they disgraced the family by dating non-Muslims and acting too Western, and she called the girls' murders an honor killing from the start.

But the FBI held off on calling it an honor killing until just recently, when it made Yaser Abdel Said the "featured fugitive" on its Web site.

"That's what I've been trying to tell everybody all along," Gartrell told FOXNews.com. "I would say that's a victory."

But some Muslims say that calling the case an honor killing goes too far.

"As far as we're concerned, until the motive is proven in a court of law, this is [just] a homicide," Mustafaa Carroll, the executive director of the Council of American-Islamic Relations in Dallas, told FOXNews.com.

He said he worries that terms like "honor killing" may stigmatize the Islamic community. "We (Muslims) don't have the market on jealous husbands ... or domestic violence," Carroll said.

The United Nations estimates that 5,000 women are killed worldwide every year in honor killings - mostly in the Middle East, where many countries still have laws that protect men who murder female relatives they believe have engaged in inappropriate activity. A U.N. report includes chilling examples of such cases.

"On the order of clerics, an 18-year-old woman was flogged to death in Batsail, Bangladesh, for "immoral behavior," the report reads. "In Egypt, a father paraded his daughter's severed head through the streets shouting, 'I avenged my honor.'"

But Islamic scripture in no way condones such actions, Carroll said.

"People have their own cultural nuances and norms from before they got their religion," he said. "This is not Islamic culture."

Regardless of whether religion itself is to blame, Gartrell said it is important that society recognizes the case as having a cultural element, just to prevent similar crimes in the future.

"That culture is so different," Gartrell said. "If people had been more educated about it, they would have known that when the girls told people, 'Dad wants to kill me' - they were serious."

Many of the threats against Sarah and Amina Said were known to their friends and classmates.

High school friends told the Dallas Morning News that the girls sometimes came in with welts and bruises, which they confided were inflicted by their father. One time, Yaser Said reportedly went into one daughter's bedroom waving a gun and making threats on her life.

After he threatened to kill one daughter in December 2007 - documented in text messages Sarah Said sent to a friend - the girls and their mother, Patricia, fled from their home in Lewisville, Texas, to Tulsa, Okla. But the mother soon had a change of heart and went back, leading to the tragedy on January 1. Some, including Gartrell, believe the mother may even have been complicit in the murders.

Dr. Phyllis Chesler, author of several books, including "The Death of Feminism: What's Next in the Struggle for Women's Freedom," said that the case fits the description of an honor killing.

"The premeditation, the family collaboration, and the particular rules (set for the girls) make this consistent with an honor killing - not just domestic violence," she said.

She said she hoped that calling the case an "honor killing" might indicate a shift in attitude at the FBI.

"I think this may suggest that law enforcement is beginning to realize that they may have to treat these incidents differently if they are to either prevent or prosecute," Chesler told FOXNews.com.

She noted that the United Kingdom has a special police unit to deal with "honor-related violence," and said that she hoped that the situation in the U.S. does not get to the point where that becomes necessary.

But an FBI spokesman played down the significance of the listing, saying that the change on the wanted listing was simply due to more information coming out about the case since it was first listed and that it shouldn't matter what the case is called.

"We're just looking at how do we find the guy?" said FBI special agent Mark White, media coordinator in the bureau's Dallas office.

Irving Police Department Public Information Officer David Tull agreed. "We just look at the facts. The man killed his two daughters. This is a domestic violence, multiple-capital murder case."

Tull said that, unfortunately, there have still been no sightings or major leads - a fact that distresses Gartrell.

"I'm very upset about it," said Gartrell, who argues that the case needs special consideration. "This is not a typical murder case. When a family member murders another family member to protect [the family] name - that's different."

Click here to see the FBI's Wanted poster for Yaser Said.

Sarah and Amina Said, were very close friends and did well in school.

On January 1, 2008, someone brutally murdered teenaged sisters Sarah and Amina Said. Police say the killer shot the girls to death in the back of a taxi cab and then fled.

The murder shocked the town of Lewisville, Texas, where the girls were from. But when police revealed the identity of the suspected killer, it shocked the nation.

Police have charged the girls' father -- Yaser Said -- with capital murder as well as unlawful flight to avoid prosecution.

"I just don't understand," said Connie Maggio, the girls' aunt. "Those girls were horrified -- they must have been -- to have their dad pointing a gun at them."

But the girls' family, like Maggio, say in order to understand the way the girls died, it's important to take a closer look at the way they lived.

On the outside, they were beautiful young women who lived with determination and grace. But on the inside, they hid a secret.

"He treats me like a whore," Sarah Said wrote in an instant message conversation wither her friend, Zohair Zaidi.

Family Secrets, Family Disaster

Before they were killed, Sarah and Amina Said told friends they had a difficult relationship with their father, Yaser.

At school, the girls were respected by their teachers and peers. They had good grades and made it clear they hoped to go to college, and then medical school. They were known for their signature smiles.

But at home, the girls confessed to friends that they shed tears more often than not, because of their difficult realtionship with their father.

In 1998, the girls filed a police report, alleging that their father sexually abused them, but they later recanted the story.

However, they did confess to a few friends that the abuse continued.

"He treats me like a whore," Sarah Said wrote in an instant message conversation wither her friend, Zohair Zaidi.

Zohair said that the girls told him they were rarely allowed to participate in after school activities and that their father controlled every move they made.

Yaser made it clear they were especially forbidden from developing relationships with boys. In fact, Zohair said Sarah had programmed his phone number in her phone as "Amanda" so her dad wouldn't be suspicious of their friendship.

Cops Charge Father With Murders

Yaser Said, wanted for killing his daughters, is pictured here on his wedding day.

However, it's what Yaser Said learned on Dec. 26, 2007, that allegedly sent him over the edge. Patricia Said told AMW that on that day, her husband learned that Amina had a boyfriend. Yaser Said was so upset, he allegedly threatened his daughters with a handgun.

Later that night, after Yaser went to work, the girls convinced their mother to run away with them. But days later, the girls and their mother returned home after Yaser Said promised to change.

Upon returning, Yaser invited his daughters to go to dinner with him. As the girls got into his taxi cab, they made it known they feared for their lives. Zohair says he received a final and haunting text message.

Sarah sent him a text message saying that they were back home and that she was worried. Zohair said he had a terrible feeling something was going to happen so he sent her a passage from the Koran, which translates as, "We are from God and to him we shall return."

It was the last time he spoke to Sarah. Shortly after, the Irving Police Department recieved a 9-1-1 call from Sarah Said saying that her father had shot her, and that she was dying.

When police found the girls, they were dead. Yaser Said fled and remains on the lam. He is 6'2" tall and weighs 180 lbs. He smokes Marlboro Light 100 cigarattes and likes to go to diners, including Denny's and IHOP.

Click here to see the America's Most Wanted Article.