A Boston man wanted for allegedly murdering two sisters in their Dorchester apartment in 2011 is now one of the most hunted men in America— and internationally.

The U.S. Marshals added fugitive Jean Weevens Janvier, 34, to their 15 Most Wanted list today. Janvier has been indicted for killing Stephanie and Judith Emile in an execution-style slaying in their apartment on Harvard Street on Nov. 14, 2011. The crime was made all the more heinous when police found a 2-year-old toddler, who was left alive but alone with their bodies.

Authorities believe Janvier — who was born in Haiti but is a U.S. citizen— fled the state soon after the murders. Police say that he should be considered armed and dangerous. His whereabouts remain unknown.

“It is difficult to imagine what kind of malicious individual could perform the unspeakable crime Jean Janvier allegedly committed that took the lives of two young sisters,” said U.S. Marshals Service Deputy Director David Harlow in a statement issued today. “The U.S. Marshals will dedicate all our available resources along with the help of our federal, state, and local law enforcement partners to bring Janvier to justice and answer for these heinous crimes.”

U.S. Marshal John Gibbons of the District of Massachusetts reiterated that commitment. “The Marshals Service is committed to assisting the Boston Police Department in locating and apprehending Jean Janvier to open the doors of justice for the Emile family.”

Janvier is a 6-foot-1-inch black male weighing approximately 150 pounds, with black hair and brown eyes. A reward is being offered for information leading directly to Janvier’s arrest. Anyone with information is urged to contact the nearest U.S. Marshals office or the U.S. Marshals Service Communications Center at 1-800-336-0102 or email usms.wanted@usdoj.gov.