It started off as a high school romance.

Mark K. Makki and Aramis Mizani were in their mid-teens when they met, both the offspring of Iranian immigrants who chose Montgomery County to escape the revolution that swept through their homeland in the late 1970s.

They were average students, relatives said. Neither was class president. Neither was class clown. Their tempered personalities clicked, and the relationship -- much to the chagrin of the boy's mother -- endured five years of highs and lows.

Now, that relationship has emerged as a possible motive in the Oct. 6 fatal beating and strangulation of Makki's mother, Shohreh Seyed-Makki, according to Montgomery police. Makki, 23, is charged with killing Seyed-Makki in their Potomac home. At the time of the arrest, police noted that Makki and his mother often clashed over his girlfriend, whom she disliked.

The killing, which authorities have declined to describe in detail, has thrust into the limelight a private feud between two families now united by intense public scrutiny and a high-profile criminal investigation.

Makki's family members say they believe he is innocent. Police say they still believe they charged the right man, despite DNA evidence from the crime scene that a law enforcement source said shows an unidentified man came into contact with Seyed-Makki shortly before she was killed.

Through his attorney, Makki declined to comment. Mizani could not be reached.

Makki's supporters acknowledge that the relationship was a sour issue for the 54-year-old victim, but they say it certainly was not one to kill over.

"Mark would choose his mom over his girlfriend, and that was clear to both parties," said Amirreza Vaziri, 24, a close friend of Makki's. "So there was never a situation where he had to choose."

Mizani, 21, met Makki a few years after her mother drowned in Ocean City in 1995. As the relationship progressed, her problems grew, her half brother Cory Levy said.

Mizani developed chronic back pain, which worsened after what Levy described as a botched surgery. The ailment became unbearable, affecting her studies and making her dependent on powerful painkillers that sometimes cloud her judgment, according Levy, 31.

In the late 1990s, her family's finances deteriorated, Levy said. Her father, Ahmad "Eddie" Mizani, a carpet salesman, was convicted of tax evasion, court records show. Deportation proceedings subsequently were initiated against him. The government often deports green card holders who have been convicted of felonies.

Greg Gagne, a spokesman for the Executive Office for Immigration Review, the judicial immigration agency, said court docket records show that immigration officials were seeking to deport Ahmad Mizani after the conviction. Gagne said the status of the immigration case could not be determined from the records he has access to. A spokeswoman for the prosecuting agency, U.S. Immigration and Customs Enforcement, declined to comment.

Ahmad Mizani also declined to comment, as did David Rothwell, his attorney in the immigration case.

"Aramis has been through a lot," Levy said. "Having had everything and then everything taken away."

After graduating from high school, neither Makki nor Mizani embarked on a solid career path.

Makki, whose father is a well-known ear, nose and throat surgeon and whose sister recently graduated from law school, attended Montgomery College sporadically during the past five years. He has received 62 credits and has not declared a major.

Makki is passionate about tennis and the stock market, two interests in which his parents indulged him. His father, Khosrow S. Makki, once gave him $600,000 to invest in stocks, according to a close relative. Khosrow Makki has declined to comment.

Mark Makki made smart investments, which he tracked closely online, often with his mother by his side, said the relative, who asked not to be identified because he fears police retaliation.

"He has a knack for picking good companies," Makki's friend Vaziri said, and he entertained the idea of getting into real estate.

But relatives feared that the youth was not reaching his full potential.

According to Makki's friends and relatives, Seyed-Makki saw her son's girlfriend as the main cause. Over the years, her distaste for the girl intensified. She wanted a college-educated bride for her son, people close to the family said. She disliked the fact that Mizani took legal narcotics to numb her back. And she felt disgraced by Ahmad Mizani's criminal record.

According to the Makkis' relative, the victim unloaded her anger on the girl's father a few times at his Derwood store, Shaaheen Oriental Rug Co., where she demanded that he forbid his daughter to see her son. He never did.

"She thought that Mark was not successful, that he was being denied a good education because of the girl," Makki's relative said. "She does [legal] narcotics. Being from a Persian family, we are very cautious about the bride."

Some deemed Seyed-Makki's staunch opposition to the relationship as absurd, oddly Shakespearian in this day and age, even in a close-knit immigrant community in which many parents still try to influence their children's love lives.

"Her life mission was to keep them apart," Levy said. "My sister is not a bad person. Was Aramis going to be a lawyer or doctor? No. Nobody was concerned about the relationship other than her," he said, referring to Seyed-Makki. He paused, then said, "She should have been more worried about what Mark was doing with his life."

Efforts to separate Makki and Mizani were futile.

Last year, Makki went to Shenandoah University, in Winchester, Va., more than 70 miles away from home. Mizani visited him at the university. This year, he spent some time in Miami, where he coached and played tennis.

"She would still fly down to Florida. They would just find a way to see each other," Levy said. "I think it's that first-love thing. Sometimes people can't get away from it."

Mizani's statements to homicide detectives hours after the killing -- which police say disproved Makki's alibi -- in part led authorities to charge him with first-degree murder and robbery.

Prosecutors have said that at police headquarters before his arrest, Makki urged Mizani to tell police they had been together at the time of the crime, a move described in court as an apparent attempt to tamper with a witness.

When police confronted him with the contradictory versions of his whereabouts on the day of the killing, Makki told detectives that his girlfriend's memory might have been blurred by the drugs she takes, according to a charging document.

Mizani attended Makki's bond hearing Oct. 11 with her father. She wept as she left the courtroom after a judge declined to release her boyfriend on bail. Ahmad Mizani, furious at photographers who took pictures of him and his daughter as they walked down the court steps, smacked a photojournalist in the face in front of numerous witnesses.

Makki was released on $250,000 bond two days later, after prosecutors acknowledged that DNA tests conducted in the case did not link him to his mother's body at the time she was killed.

A judge ordered that he surrender his passport and forbade him to leave the state, except to attend his mother's funeral, which was in Virginia on Oct. 15.

Makki wore a dark suit to the funeral. Mizani attended with a mutual friend; her father was not there. The weather was splendid -- in sharp contrast to the mood of a family doubly bruised in the space of a week by a slaying and arrest.

"In a weird way, I wish the cameramen were there," said Vaziri, who was present. "Because Mark was so good-looking that day, not like the [mug shot] that was posted on every paper. And he was crying, and you could see his pain and his innocence."

When the service ended. Mizani walked toward Makki, Vaziri said. Makki's relatives huddled around him before she reached him and whisked him to a car waiting nearby.

Mark K. Makki is charged with killing Shohreh Seyed-Makki.Aramis Mizani leaves the courthouse with her father, Ahmad Mizani, after an Oct. 11 bond hearing for Mark K. Makki.