Honolulu police launched a first-degree robbery investigation of a 67-year-old victim in Kalihi late Monday.
Police said a male suspect approached a man on a street and used an unknown object to threaten him about 11 p.m. Monday. Police did not disclose the street name.
The suspect allegedly took property from the victim and fled.
A description of the culprit was not immediately available.
There are no arrests at this time.