Prosecutors said Hernandez felt disrespected after a stranger bumped into him and spilled his drink, prompting him to follow the man and his friends, then open fire on their car at a red light.
"I think I got one in the head and one in the chest," Hernandez told a friend as they fled the intersection, prosecutors said at the former gridiron star's arraignment.
Hernandez, already charged with killing another man last year, pleaded not guilty Wednesday to seven charges -- including two counts of first-degree murder -- in the July 2012 shooting that killed Daniel de Abreu and Safiro Furtado. A third man was wounded.
In the months before the killings, Suffolk County First Assistant District Attorney Patrick Haggan told the court, Hernandez had become increasingly convinced that people "had been testing, trying or otherwise disrespecting him when he frequented nightclubs in the area."
The night de Abreu and Furtado were killed, Haggan said, Hernandez and a friend drove from Connecticut to a Boston nightclub called Cure. They were standing at the edge of the dance floor when de Abreu accidentally bumped into Hernandez, smiled at him and did not apologize, according to prosecutors. Haggan said de Abreu and his friends did not appear to recognize Hernandez and had no idea he was upset.
Hernandez became increasingly agitated and told his friend that de Abreu had deliberately bumped into him and "was trying him," Haggan said.
Surveillance video outside the club shows Hernandez pacing back and forth on the sidewalk as his friend tries to calm him down, Haggan said. Hernandez and his friend then crossed the street to another nightclub, where Hernandez thought he saw de Abreu and his friends come in, according to Haggan.
Hernandez then told his friend he believed he was "being targeted and being disrespected," Haggan said. In fact, de Abreu and his friends had not left the other club.
Haggan said Hernandez later drove around with his friend until he saw de Abreu, Furtado and others going to their car, then followed them and pulled up alongside their car at a red light.
"At this time, the victims were completely unaware there was any problem with the defendant," Haggan said.
Hernandez leaned out the driver's side, said, "Yo, what's up now," followed by a racial slur, then fired at least five shots into the car, killing de Abreu and Furtado, and injuring a man sitting in the back seat, Haggan said.
Hernandez's attorney, Charles Rankin, objected, saying the prosecutor's account of the shooting was an attempt to poison the jury pool. Clerk Magistrate Gary Wilson dismissed the objection, saying it is standard procedure for prosecutors to describe evidence during arraignments in murder cases.
Family members of those killed filled four rows in the courtroom. One woman sobbed loudly as Hernandez entered his not guilty pleas.
De Abreu and Furtado were close friends who attended school and served in the military together in Cape Verde before coming to the United States, according to the attorney who represents their families in a $6 million civil suit against Hernandez.
The two men were shot about six weeks before Hernandez signed a five-year, $40 million contract with the Patriots. He went on to catch 51 passes and score five touchdowns that season, his last in the NFL.
Hernandez, 24, was released by the Patriots last summer after he was charged in the June 17 killing of semi-pro football player Odin Lloyd, who was dating a sister of Hernandez's fiancee. Lloyd's body was found in an industrial area near Hernandez's home in North Attleborough.
Hernandez's lawyers have said he is looking forward to proving his innocence.
Suffolk District Attorney Daniel Conley would not comment when reporters asked whether Lloyd's killing was linked to the earlier killings of de Abreu and Furtado. He said Lloyd was not the friend who was with Hernandez the night the two men were killed.
Hernandez will continue to be held without bail. He is due back in court June 24 for a scheduling hearing.