Twin bombs detonated near the finish line of the beloved Boston Marathon on Monday left over 140 people injured and at least three — including a little boy — dead. The FBI heads an ongoing investigation into who planted these bombs and whether the terrorist(s) involved are foreign or domestic. Many faces, some unfamiliar to most Americans, lit up the evening news circuit in response to the attack. These are the key players at the heart of the Tax Day bombing — people to keep an eye on in the coming weeks as a shell-shocked city puts the pieces back together again.

Boston Mayor Thomas Menino had given nearly five long terms to the mayoral office (the longest reign in the city’s history), and at 70 years old, was ready for a well-deserved rest. Several weeks ago in Boston’s Faneuil Hall, he announced he would not be seeking a sixth term due to exhaustion from the packed schedule he usually keeps. Just four days before two bombs hit his city, he slipped outside an event in Dorchester and broke his leg, undergoing surgery to repair that leg just two days before the event. Despite recent stints of poor health, which have even prompted speculation that he might step down from office early, Menino wore a brave face Monday and kept in touch with all manner of officials, from first responders to his own Massachusetts governor to President Obama to well-wishers like Rahm Emanuel.

Massachusetts Governor Deval Patrick won his post handily back in a 2006 race that made him the first African-American governor ever to helm his state. Then-Senator Barack Obama even admitted to lifting some of his hope-change rhetoric from Patrick’s stump speeches when he first ran for the presidency in 2008. Since then, the two-term governor has been quietly battling a Republican-controlled legislature for initiatives such as tax hikes, education and building resort casinos. Making few inroads, his first-term policy agenda even descended into insult-trading with former House Speaker Salvatore DiMasi. All that must seem like petty child’s play now, as the nation’s eye is trained on Patrick in the wake of America’s first major bombing since 9/11. In a statement responding to reports of the explosions, Patrick said: “This is a horrific day in Boston. My thoughts and prayers are with those who have been injured.”

Boston Police Commissioner Ed Davis took command of the police force in 2006 and wasted no time cleaning up his city. He decreased ‘serious’ crimes by 18% and slashed shootings by 40% in his first three years as Boston’s top cop. Though his son was arrested for DUI back in February, causing a minor public scandal, Davis has long projected strong values and has largely stayed out of the limelight — until now. Working tirelessly alongside the rest of his police force to secure the streets in the immediate aftermath of the attack, Davis appeared at several press conferences to dispense the most current information he could. He also denied media reports of a suspect being held at a local hospital.

Lisa Monaco, a relatively unknown national security voice, is President Obama’s Deputy National Security Advisor for Homeland Security and Counterterrorism. She is a new face in Obama’s circle now that John Brennan has been confirmed as CIA director, and as the adviser who briefed Obama on the attack Monday afternoon, her skills are about to be put to be the test. She has traveled to Gitmo with Eric Holder, prosecuted Enron, and served as chief of staff to FBI Director Robert Mueller.