Masked gunman on the run after fatally shooting two teenagers in the head outside Chicago high school

Gunman – who was dressed in all black with a mask, hoodie and North Face jacket – remains at large after fleeing the scene on foot

A masked gunman fatally shot two teenagers in the head and wounded two others outside a Chicago high school, just minutes after classes had ended for the day.

Gunfire erupted when students were leaving Benito Juarez High School on the southwest side of the city at around 1430 local time [GMT 2030] on Friday.

Two teenage boys – Brandon Perez, 15, and a 14-year-old boy who has not been named – were shot in the head in the attack, Chicago Police said.

They were rushed to hospital but were pronounced dead from their injuries.

Two other teenagers, a 15-year-old boy and a 15-year-old girl, were also shot but survived.

The boy suffered gunshot wounds to the shoulder and thigh while the girl suffered a bullet graze to the thigh. They remained in stable condition in hospital.

As of Saturday morning, the gunman remains at large with no arrests made and no suspects identified.

“We are early in this investigation,” Chicago Police Supt David Brown said in a press conference on Friday.

Police said the gunman – who was dressed in all black with a mask, hoodie and North Face jacket – fled the scene of the shooting on foot.

Grabs from surveillance footage capture the assailant running from the school in the aftermath of the attack with police asking for the public’s help in identifying the individual.

The motive for the attack remains unclear.

A source close to the school told CBS Chicago that he believed the three male victims had been targeted by the shooter but that the girl was simply caught in the crossfire.

Chicago Police are looking for this individual on suspicion of shooting four teens (Chicago PD)

While police and school officials have refused to confirm whether or not all four victims were students at Juarez, the source claimed that they were.

One eyewitness told the local outlet how he initially mistook the sound of gunshots for fireworks.

Nicasio Rogel, whose child is a sophomore at the school, told WBBM he heard six to eight gunshots and then saw two teenagers lying on the ground. They were still wearing their school backpacks.

“I feel sick. I feel angry because these are things that should not be happening in school,” he said.

Illinois governor JB Pritzker condemned what marks the latest “senseless gun violence” to rock an American community as he sent his regards to the victims’ families.

“Schools are the cornerstone of neighborhoods and students deserve to feel safe. Earlier today, senseless gun violence took the lives of two people outside of Benito Juarez High School and injured two more,” he said in a statement on Twitter.

“My heart goes out to the family and friends of those who lost their lives today and I pray for a full recovery for those injured. MK and I are thinking of the entire Benito Juarez community. We must put an end to these unspeakable tragedies and rid our communities of gun violence.”

Anyone with information about the shooting is asked to contact the Area Three Bureau of Detectives at 312-744-8261 or cpdtip.com. Tipsters can remain anonymous.