Two young men and a juvenile were arraigned today in connection with a near-fatal stabbing last week in the heart of downtown Boston that left a portion of the nation’s oldest city park sealed off with crime scene tape, Suffolk County District Attorney Daniel F. Conley said.

JOHNNIE BONNIE (D.O.B. 6/28/92), JERMAINE GILLESPIE (D.O.B. 10/28/93), and a 15-YEAR-OLD MALE who is not being identified because he is a juvenile were all charged this morning with armed assault with intent to murder for their alleged roles in the incident, which unfolded near the intersection of Tremont and Park streets as rush hour began Friday evening.

The three are additionally charged with two counts of assault and battery with a dangerous weapon for allegedly kicking and stabbing the 18-year-old victim, and single counts of carrying a dangerous weapon.

Calling the group attack “brazen and vicious,” Assistant District Attorney Gregory Henning of Conley’s Major Felony Bureau recommended that each defendant be held on $200,000 cash bail. Boston Municipal Court Judge Edward Redd set that bail for Bonnie and Gillespie, as Boston Juvenile Court Judge Marjory German did in a separate proceeding for the juvenile.

Henning told the court that the assault was not random in that the victim and defendants knew one another.

Henning said the defendants attacked the victim near a Tremont Street 7-Eleven just before 5:30 p.m. Two civilian witnesses saw the attack and “observed the two defendants and the juvenile punching and kicking the victim.” Those witnesses later described the assailants as three young black men wearing white shirts, with two wearing tan shorts.

The victim sustained five stab wounds to his chest, abdomen, shoulder, and back, Henning said, which corresponded to the locations where witnesses said the assailants were punching him.

The victim stumbled away from his attackers, Henning said, first to the exit alcove of a Park Street station exit and then across the street to the area in front of the station’s main entrance, where he collapsed. His attackers fled on foot. A knife found near the scene was later recovered by a civilian who turned it over to police.

MBTA Transit Police gave a brief chase after the suspects, but ran back to the scene to provide emergency first aid to the victim. They were joined by Boston Police and emergency medical technicians, who rushed the victim to the hospital for surgery. He was admitted in critical condition with a stab wound just inches above his heart but is now expected to survive.

One of the civilian witnesses, Henning said, grabbed his girlfriend’s camera and began snapping photographs of the assailants as they ran from the scene. That witness turned the photos over to police. Investigators also had access to video from MBTA surveillance cameras, which showed individuals matching the witness descriptions exiting Downtown Crossing station shortly before the stabbing and Ruggles station about 40 minutes afterwards.

After circulating the photographs and images among local law enforcement agencies, Boston Police identified the defendants, obtained warrants for their arrests, and sought them at their parents’ homes. They had no success. Gillespie should have been in Department of Youth Services custody at the time of the attack, Henning said, and that agency sought its own detainer on him.

Boston Police were then led to a Dacia Street residence, where the Youth Violence Strike Force set up surveillance and saw the defendants yesterday. When the defendants saw the officers, they ran back inside. Officers pursued them and placed them under arrest, then froze the apartment pending a search warrant.

At the time of the arrests, all three were wearing clothing and other items depicted in the surveillance and civilian images, Henning said, and the juvenile was additionally carrying a knife. The clothing of all three was seized and found to have reddish-brown stains consistent with blood spatter. Those stains will be tested.

The juvenile was represented by attorney Stephen Weymouth. Bonnie is represented by attorney Neil Madden and Gillespie by attorney Tim Brown. All three will return to court on June 16.