SAN ANTONIO – San Antonio police arrested a suspect in the shooting death of a 14-year-old boy on the Southeast Side in July, according to an arrest affidavit.

Police arrested Gideon Segundo, 17, on Monday. He was charged with capital murder of a person older than 10 years of age but younger than 15 years of age in the death of Timothy Chavez, the arrest documents stated.

Chavez was shot multiple times at 11:45 p.m. on July 15 in the 3800 block of South Mittman Street, not far from Fair Avenue and Goliad Road.

Video footage showed a maroon sedan pull up to Chavez’s home as he walked up to the street, the arrest affidavit said. Shortly after, several shots were heard in the video, and the sedan sped away.

When family members came out after hearing the shooting, they found Chavez with gunshot wounds to his head and upper torso, police said. He was pronounced dead at the scene.

Further investigation revealed Chavez was attempting to sell a firearm via Instagram, according to arrest documents.

Family members did not see the AR-15 pistol Chavez was attempting to sell after the shooting, documents revealed.

Police found 21 spent rifle casings at the crime scene.

Officers later learned Segundo was an acquaintance of Chavez and would frequently purchase marijuana from him. They also found out Chavez had a maroon vehicle, which was parked next to an address that was linked to Segundo, according to the documents.

Video surveillance later captured the maroon sedan, later identified as a Mitsubishi Galant, one block away from the murder scene and also traveling through Mittman Street.

Detectives were able to seize the Galant to preserve evidence in the vehicle. After further investigation, they found human blood drops in the car.

Police also confirmed Chavez and Segundo set up a deal to sell the firearm at Chavez’s house. The time stamps matched the time of the shooting, records show.

Segundo told officers about three separate shootings at his home in the past month and said he believed they stemmed from him and his brother messing with people in the streets in their neighborhood, the arrest affidavit said.

The suspect also told officers he was forced to lend his car and phone to someone else who wanted to rob Chavez, but he later changed his story several times during questioning, police said.

After investigators questioned the inconsistencies, Segundo refused to talk.

Police said they determined Segundo was the person who shot and killed Segundo after not finding any other messages between him and anyone else related to robbing Chavez.