FILE – This combination of undated family photos shows, from left, Martin Richard, 8, Krystle Campbell, 29, and Lu Lingzi, a Boston University graduate student from China, all who were killed in the bombings near the finish line of the Boston Marathon on April 15, 2013, in Boston. Jury selection for the trial of bombing suspect Dzhokhar Tsarnaev is scheduled to begin Monday, Jan. 5, 2015, in federal court in Boston. (AP Photo/File) BOSTON — Potential jurors stared intently at Boston Marathon bombing defendant Dzhokhar Tsarnaev as jury selection began under tight security Monday in one of the nation’s most closely watched terror cases since the Oklahoma City bombing two decades ago.Tsarnaev, flanked by his attorneys, sat at a table at the front of the jury assembly room. Wearing a dark sweater and khaki pants, he looked down much of the time but occasionally glanced at the potential jurors and the judge. He also picked at his shaggy beard.When U.S. District Judge George O’Toole Jr. introduced him and asked him to stand, he acknowledged the group with an awkward nod.Tsarnaev, 21, is accused of planning and carrying out the twin pressure-cooker bombings that killed three people and wounded more than 260 near the finish line of the race on April 15, 2013.Over the next three days, a larger-than-normal pool of about 1,200 people will be summoned to federal court to be considered as potential jurors. The first 200 were given initial instructions Monday by O’Toole. Twelve jurors and six alternates will be selected.