Authorities said the shooting happened near an apartment complex on Bammel N. Houston, shortly before 3 p.m.
The suspect has only been identified as a 15-year-old, deputies said. He was reportedly detained inside the apartment complex where the shooting occurred.
ABC13's SkyEye was over the scene where several police cruisers and yellow tape lined the outside of the complex, with bystanders looking on.
Sheriff Ed Gonzalez posted on social media that CPR was administered to the victim, but he died at the scene.
Investigators said they have not found a motive for the shooting, but they believe it stemmed from some kind of drug transaction.