NEW YORK -- A teen-ager from Colombia was convicted yesterday of being the gunman who calmly pumped two shots into the head of a journalist who had earned the wrath of the Cali drug cartel.

Wilson Alejandro Mejia-Velez, who turned 19 yesterday, showed no emotion as a jury in federal court in Brooklyn found him guilty of killing Manuel de Dios Unanue on March 11, 1992, before the journalist could complete a book on the deadly cartel.

Mr. de Dios' companion, Vicky Sanchez, who broke into tears on hearing the verdict, told reporters that the final chapter on the 49-year-old editor's murder will not be written until the drug kingpin who signed his death warrant is brought to trial. Jose Santacruz Londono, the alleged head of one of the Cali cocaine organizations, has been charged in connection with de Dios slaying, but not apprehended.

"I don't know when, tomorrow or the day after tomorrow, but I definitely hope to see him in a trial," she said. "In five or 10 years, I hope I can tell my daughter, 'Your father was killed because he was fighting against drugs. Because he was trying to clean our community, trying to help our people. . . . But the people who killed your father, they are all in jail.' "

The verdict came after only seven hours of deliberations by a jury that asked few questions of U.S. District Court Judge Edward Korman. Thirty minutes before the verdict, it requested the definition of "reasonable doubt."

As the jury filed out of the courtroom, Mejia-Velez shook his head in disbelief. His mother, Rosalba, burst into sobs and said: "I'd rather have been killed, too. Kill me, too."

Mejia-Velez, who immigrated to the United States illegally to work in a New York chair factory for $5 an hour, could be sentenced to life without parole. Judge Korman set no date for sentencing.

Eric Friedberg, an assistant U.S. attorney, said it was not likely that Santacruz Londono would ever stand trial since there is no extradition treaty between Colombia and the United States.