A group of gang members armed with machetes and knives. A teenager hunted down and dragged from a New York City bodega, then swarmed by attackers outside. The vicious murder in June of Lesandro Guzman-Feliz just blocks from his Bronx home drew outrage from across the city and beyond. The incident revealed the barbaric tactics of a gang called the Trinitarios, and it laid bare a glaring paradox: Amid historically low crime rates in New York, police are still struggling to contain brutal violence in some neighborhoods. The footage went viral and with it, rumor and speculation about why the 15-year-old boy known as Junior was singled out. We obtained footage from multiple security cameras and cellphones. We talked to police sources, family members and other witnesses. Our investigation retraces Junior’s last steps and uncovers new details that may answer why he was targeted. It’s Wednesday, June 20. Junior is on summer break from school. He’s at home with his mother. At 10:05 p.m., security footage shows Junior leaving home to meet his friend Jason Velez at this corner. They hang out on a stoop close by, chatting and listening to hip-hop, according to Jason. At around 11:30, Junior leaves, and two minutes later security cameras catch him on this corner passing near his home. He was walking toward Adams Place, a small street about five minutes away that’s known for gang activity. Friends and family told us that Junior wasn’t in a gang and the police have no such indication, either. But some of his friends were, and he had been hanging out with them at Adams Place recently. On his way there, Junior was in touch with this friend, who lives on Adams Place and who, according to our reporting, is not in a gang, either. The friend says he told Junior not to come over because it was late. At 11:35, a security camera films four cars driving slowly past the stoop where Junior’s friend and some others were sitting. The friend says they felt things were getting dicey and went inside. The cars briefly stop at this intersection, and then turn left in the direction of Junior’s path. According to police, the drivers spot Junior and taunt him. Junior begins to run and the cars give chase. The cars then split up and appear to surround him. It’s 11:37. Junior rushes into this bodega just one block from his home. In a panic, he tries to hide behind the counter. But it’s too late. One man, identified by prosecutors as Jose Tavarez, enters the bodega and spots Junior. He’s been charged with these crimes. He leaves and immediately three other men enter. Police have identified them as: Danel Fernandez, Kevin Alvarez, and Michael Sosa Reyes, who has not been charged in relation to Junior’s killing. Parked outside the bodega are the cars that chased Junior. At least eight other men are on the lookout — some, armed with knives. A warning: These next scenes are hard to watch, and we’ve obscured some graphic parts. Junior and the bodega owner appear to have an exchange with Kevin Alvarez before Junior is grabbed and beaten on the ground. Then he’s dragged from the bodega and brutally stabbed by a swarm of attackers. According to prosecutors, José Muniz first hacks Junior with a machete. Then, Elvin Garcia, who police say is seen here wearing a mask. Manuel Rivera is accused of repeatedly stabbing Junior. Antonio Santiago is seen here from this other angle. Prosecutors say that Jonaiki Martinez gave the fatal stab, slashing Junior’s neck. Five other people have been arrested and accused of involvement in the crime. All of the men charged have pleaded not guilty. It’s 11:39. Junior stumbles back into the bodega, leaving a trail of blood on the floor. But the owner appears to direct him away. Junior gestures for someone to call 911. Then he starts running to St. Barnabas Hospital, just one block away. He makes it to the entrance of the hospital before collapsing. Passersby try to help. Witnesses say these two police officers stood by watching the scene. They are under investigation for failing to help. Just 20 minutes later, Junior is pronounced dead as a result of a stab wound to the neck. How Junior was killed follows a pattern of attacks by Trinitarios, a Dominican gang that was born in New York prisons. In recent months, turf wars have spiked among rival Trinitario factions. At least 10 other people have been maimed this summer in tit-for-tat attacks in the Bronx. Just two days before Junior was killed, a 14-year-old was seriously injured in this attack. And on the night before Junior’s murder, he had witnessed another stabbing at Adams Place. Junior’s friend, a Trinitario, had been attacked by a rival faction and allegedly turned to Junior for help. Is that why Junior was targeted? We don’t know. But a leading police theory is the attackers mistakenly believed Junior was in a rival gang. What we do know is that for Junior — like many teenagers growing up in gang-afflicted areas — there’s a fine line between hanging out on the streets and getting caught up in deadly violence.