(CNN)  New Jersey's largest newspaper had some tough words Sunday for Sen. Bob Menendez as he faces allegations of improper travel and parties with prostitutes. The same paper endorsed the senator's bid for re-election three months ago.

An editorial in the Newark-based Star-Ledger said the accusations raised "serious doubts about his fitness to serve as Chairman of the Foreign Relations Committee" and argued he "needs to break his silence and explain himself."