Melissa Barthelemy, 24, was last seen alive July 12, 2009, and her sister in Buffalo, N.Y., got calls from her cellphone on July 16, 19 and 23, law enforcement sources told the New York Daily News.
"Do you know what your sister is doing? She's a whore," a man's voiced taunted.
New York police traced the last two calls to Midtown Manhattan.
The New York Times, citing a law enforcement official, reported that Barthelemy's telephone records were traced to the Budget Inn and the Best Western motels near Massapequa, about 15 miles from Gilgo Beach, where the bodies were found in December.
Investigators checked video records at both motels and talked to staff but learned nothing, the official said.
Barthelemy's family called police in New York soon after she disappeared from her Bronx apartment.
Police subpoenaed phone records, scoured the neighborhood and gathered DNA evidence, including a toothbrush that was later used to identify the body.