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Heller is undecided on the Senate health care bill

Washington (CNN) Las Vegas police discovered a "threatening note" at Republican Sen. Dean Heller's office on Sunday after responding to a burglary alarm at the building where his office is located.

The Las Vegas Metropolitan Police Department told CNN in a statement that they received a call from an alarm company representative at a little after 9 a.m. reporting the alarm at the building's main entrance had gone off.

The preliminary investigation by police determined that a burglary did not occur to the main building or Heller's office, but the threatening note addressed to Heller was discovered near his office door, authorities told CNN.

Officers took a report for the letter and are investigating the incident, they said.

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