FBI widens net in hunt for Brown University shooter

Colonel Oscar Perez, chief of the Providence Police Department, speaks during a press conference into the ongoing investigation into the December 13 mass shooting at Brown University. [AFP]

FBI experts on Tuesday combed through the vicinity of a weekend mass shooting that killed two students at the elite Brown University, as the hunt for the gunman dragged into a fourth day.

Images posted by the bureau on social media showed laboratory specialists  and evidence response teams conducting a forensic search on the snow-covered grounds outside the Providence, Rhode Island campus.