A Dorchester Municipal Court judge today rejected arguments from lawyers for a 14-year-old and a 16-year-old that they posed no flight risk after being charged with gunning down another teen and ordered them held without bail.

In a tense courtroom, Assistant Suffolk County District Attorney Jennifer Hickman said Rashawn Moody, 14, and Dushawn Taylor-Gennis, 16, patiently waited at the intersection of Washington and Fuller streets Wednesday evening for Jonathan Dos Santos, 16.

Hickman said surveillance video shows the two relaxed as they paced - laughing, chatting, even occasionally looking up at the camera that was recording them as they set the "trap" to await their "prey."

Around 7:51 p.m., Hickman said, the two split up - one stayed near the Fulller Market, the other crossed the street and crouched down. Not long after, Dos Santos approached the intersection on his bicycle, she said. The teen who had stayed - Hickman did not specify which one - made a gesture that appeared to startle Dos Santos. The other teen stood up, she said, and fired five shots. One hit Dos Santos in the neck. Mortally wounded, Dos Santos managed to pedal a short distance before falling off the bike and collapsing, she said.

Hickman did not specify a possible motive for the murder.

Attorneys for the two teens argued they should be released on, at most, $5,000 bail. Both lawyers said that not only are their clients innocent, they both are lifelong Boston residents, their families packed one side of the courtroom and they voluntarily talked to police.

Moody's lawyer in particular emphasized his client's innocence and said the cops got the wrong kid. Attorney Michael Bourbeau noted that the initial BPD release on the murder said police were looking for two suspects "in their late teens or early twenties," which his client isn't.

After briefly considering the requests, Judge Thomas Kaplanes ordered them held without bail - common in murder cases - at least pending a probable cause hearing on July 15. Although the two are being charged as adults, they will be held in DYS facilities through their trials and, if they are found guilty, until they turn 18, the Suffolk County District Attorney's office says.

During the hearing, both defendants stood behind doors, out of sight of the courtroom. Court officers lined the courtroom to ensure the families of the three teens did not mingle - both during the hearing and as they filed out.