BOSTON (CBS) – Boston Police Commissioner William Evans and Mayor Marty Walsh urged the community to come forward Thursday with information that leads to the arrest of the person who shot and killed 17-year-old Raekwon Brown in Dorchester a half a block from his school.

Evans said police worked throughout the night searching for the gunman who killed the Jeremiah E. Burke High School student and left three others injured Wednesday afternoon.

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Fellow students gathered at the site of the shooting on Thursday.

Raekwon Brown was shot and killed outside a Dorchester school (WBZ-TV)

Raekwon Brown was shot and killed outside a Dorchester school (WBZ-TV)

“He was good to hang out with never got in trouble in school, good grades he was always there,” student Anna Rich said of Raekwon.

When the bullets flew Wednesday, two of Raekwon’s cousins were also injured including 17-year-old Eric McKoy. The shooting took place outside a pizza restaurant not far from the school.

Eric McKoy was injured in a shooting in Dorchester (Family photo)

Eric McKoy was injured in a shooting in Dorchester (Family photo)

“There are plenty of people who know what happened yesterday. They’ve got to look at their conscience and step up to the plate here and give us the information,” Evans said. “Enough with the ‘stop snitching’ stuff. We’ve got a mother who lost her 17-year-old child. Step forward, have some courage and solve this one.”

The demand for information is being echoed by members of the clergy.

“Now is time for the black community to step up,” said Rev. Eugene Rivers. “You can’t use the rhetoric of black lives matter and then when a black life is lost, you’re MIA.”

Boston Police Commissioner William Evans pleaded for witnesses to come forward in the shooting death of a 17-year-old Dorchester student. (WBZ-TV)

Boston Police Commissioner William Evans pleaded for witnesses to come forward in the shooting death of a 17-year-old Dorchester student. (WBZ-TV)

“We can’t let this go. The person who had the desire to shoot someone in the middle of the day like this certainly will do it again,” said Walsh. “So we want to get these people off the street, in front of the court and get them prosecuted and sent to jail. They should not be roaming the streets today.”

Superintendent of Schools Tommy Chang said administrators have to make sure Burke students are “mentally and emotionally safe.”

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“The kids are going to be safe at school,” Chang said. “Our job is to bring normalcy to this school today.”

A teen was shot outside Jeremiah E. Burke High School in Dorchester (WBZ-TV)

A teen was shot outside Jeremiah E. Burke High School in Dorchester (WBZ-TV)

Evans said Brown’s death was not a drive-by shooting, and it appears to have stemmed from a dispute that moved down the street from the school.

Detectives are looking into whether or not the shooting is gang-related.

“We know there are students who know exactly what happened. Unfortunately they’re not coming forward,” said Evans. “Everyone should be outraged with what happened yesterday. Shame on everybody if the parents and kids don’t step up here. We can’t tolerate it.”

Police said anyone who comes forward with information will be protected.

Boston Mayor Marty Walsh urges the community to come forward to help stop violence in Boston. (WBZ-TV)

Boston Mayor Marty Walsh urges the community to come forward to help stop violence in Boston. (WBZ-TV)

Walsh told reporters that throughout the summer, police and city officials will be visible in the community trying to stop violence.

“We should be angry about the violence on our streets,” Walsh said. “We need to make sure we take our streets back.”

Evans reinforced that police will be unable to stop violent acts like Wednesday’s shooting without the public’s help.

“This is a tragedy. But maybe this is a wake-up call for everyone to help us,” Evans said. “It’s not just the police. It has to be everyone.”

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WBZ NewsRadio 1030’s Carl Stevens reports