Mar. 28, 2014 -- One of America's most wanted fugitives has been captured in Nicaragua and is on a flight to New York, where he is expected to appear in court on Monday.

The name Juan Elias Garcia hardly settled on the FBI's 10 Most Wanted list when the 21-year-old, nicknamed "Cruzito," surrendered sometime Thursday at the U.S. Embassy in Managua, Nicaragua, a law enforcement official familiar with the matter told ABC News.

Garcia’s alleged fellow gang members in MS-13 told him to turn himself in because they didn’t want added attention that results from being named one of the FBI’s 10 Most Wanted, the source said.

The FBI named Garcia one of its most wanted fugitives on Wednesday, putting out a $100,000 reward for information leading to his capture.

He was wanted for the 2010 execution-style murder of a 19-year-old woman and her 2-year-old son in Central Islip, N.Y., officials said.

“Juan Elias Garcia was placed on the '10 Most Wanted Fugitives' list because of the heinous nature of his crimes," said FBI Assistant Director-in-Charge of the New York Field Office George Venizelos. "The pressure generated by this publicity was too much for Garcia to bear, resulting in his surrender and return to the United States."

Garcia is alleged to be a member of the violent Mara Salvatrucha gang, known as MS-13, and is from El Salvador.

"MS-13 is the most violent gang here of any of the street gangs,” said Special Agent Reynaldo Tariche, who investigated the case with other members of the FBI’s Long Island Gang Task Force.

While gang-related murders are not uncommon on Long Island, "the execution of a 2-year-old and his mother is a new low even for MS-13," Tariche said.

Garcia, who was 17 at the time of the murders, had a romantic relationship with the victim, Vanessa Argueta. She had ties to a rival gang. The two had a falling out and it was decided to retaliate against her, authorities said.

"They were going to kill her for disrespecting the gang," said Special Agent James Lopez. "It is unacceptable for MS-13 members to have girls they associate with be involved with rival gang members."

The circumstances of Garcia's arrest weren't immediately known, but a source familiar with the matter said the addition of his name on the 10 Most Wanted list made a difference.

Since it was established in 1950, 501 individuals have been named to the list -- the vast majority of which were apprehended or located.

United States Attorney for the Eastern District of New York Loretta E. Lynch extended her sincere appreciation to the FBI and other law enforcement agencies that assisted with Garcia’s capture and return to the United States.

"We hope his capture brings some measure of consolation to the Argueta and Torres families," Lynch said.