CENTRAL ISLIP - The fugitive who was briefly on the FBI's Most Wanted list for his role in the deaths of a young mother and her son appeared in court today and pleaded not guilty to murder, conspiracy and other charges.

Juan Elias Garcia, 21, was arrested in Nicaragua last week, just a day after the FBI added him to its Top 10 Most Wanted Fugitives list. Federal authorities say Garcia turned himself in at the urging of his family.

Garcia is accused of being part of a group of MS-13 gang members who killed 19-year-old Vanessa Argueta execution-style back in 2010. Argueta's 2-year-old son was also killed. Prosecutors say the group killed the boy so he wouldn't grow up to one day seek revenge. Garcia allegedly lured Argueta to her death because she had befriended a rival gang.

More than two dozen of Argueta's grieving family members appeared in court today for Garcia's arraignment. They sobbed and gasped out loud as Garcia entered his plea of not guilty.

Despite the plea, federal prosecutors say Garcia has signed a written confession admitting that he was one of the shooters.