Bartow, FL -- A Polk County jury has found Alejandro Baez-Garcia guilty of murdering Juan castillo in January 2011.

As the trial was about to get underway, there was a snag.

The court had to figure out what to make of a letter - written by someone claiming to be the "real" killer.

Once resolved, the trial continued, and on Thursday, jurors convicted Baez-Garcia, now 20, of first degree murder.

Baez-Garcia was accused of killing Lakeland teenager Juan Castillo and critically injuring Castillo's 11-year-old brother, Jake.

At the time, Polk County Sheriff Grady Judd said the pair had been targeted because Juan Castillo was wearing rival gang colors.

Deputies who arrested Baez-Garcia said he later confessed to the shooting, telling them the shooting happened as a van drove past the victims' house.

Sentencing is scheduled for February 1st.

SEE ALSO: Bail denied for teen in weekend gang shooting