NEW YORK — Cops are planning to grill Mary-Kate Olsen about frantic phone calls she received from the masseuse who found Heath Ledger dead in his bed, The New York Post reported.

It also emerged Thursday that the masseuse, Diane Lee Wolozin, had phoned Olsen four times using the “Brokeback Mountain” star’s cellphone — three before she even considered calling 911, police said.

Emergency workers arrived about 23 minutes after Wolozin first discovered Ledger unresponsive in his bedroom near opened packages of prescription pills, sources told the Post.

Police investigators say they plan to interview Olsen — who so far has said nothing publicly about her relationship with troubled star.

Wolozin apparently knew both Ledger and Olsen and that they were friends; all the calls were made from Ledger’s cell phone.

Cops planned to ask the former “Full House” star for her account of the cellphone calls she received from Ledger’s SoHo apartment, a source told the Post.

The four calls were made during a nine-minute lag — before anyone thought to call 911.

Police also intended to ask Olsen, 21, why she sent a team of bodyguards to the apartment.

Wolozin, 40, telephoned Olsen after she and the actor’s housekeeper, Teresa Solomon, found Ledger face down on his bed. They had gone into his bedroom after he failed to respond to cellphone calls.

They were trying to rouse him for a scheduled massage appointment.

“Heath is unconscious. I don’t know what to do!” Wolozin screamed in her first call to Olsen, cops said.

Olsen replied, “I’m sending my private security there.”

Wolozin called Olsen again after finding Ledger was cold to the touch, and told the “Full House” star she was calling 911.

“I think he may be dead,” a shaken Wolozin said.

Olsen replied, “I already have people coming over.”

In all, police said Wolozin made three brief calls to Olsen between 3:17 p.m. and 3:24 p.m. She called 911 at 3:26 p.m.

Wolozin phoned Olsen again at 3:34 p.m., a minute after paramedics arrived. Olsen’s security guards arrived at about the same time.

It was unclear why Wolozin called the actress before dialing 911, why Olsen didn’t advise Wolozin to make the call for help, or why Solomon didn’t place the 911 call before the calls went out to Olsen.

Law-enforcement sources told the Post they did not think there was anything suspicious about either Wolozin’s or Olsen’s conduct.

“We have no problem with her calling [Olsen before 911],” one source said.

“This happens with everyday people, they call relatives [during emergencies] before they call 911 all the time.

“Maybe [Wolozin] panicked, because he’s a celebrity. She was afraid.”

Those sources also pointed out that there was not a big gap in time before Wolozin found Ledger and when she called 911.

When emergency workers arrived, they found Wolozin attempting cardiopulmonary resuscitation on Ledger under instruction from a 911 dispatcher.

Another source told the Post that Olsen’s security guards, who already have been interviewed by cops, “answered every question.”

“There was never anytime when those security guards were left alone” in the apartment, the source noted, pointing out that the EMTs, firefighters and cops all were at the scene.

The cause of Ledger’s death — which was followed by reports that he had been abusing illegal drugs in the past year — was still unknown Friday as authorities awaited the results of toxicological tests.

At the time of his death, the actor was said to have been exhausted and jet lagged.

He had flown to New York from London last weekend after wrapping up shooting scenes in England for a movie, “The Imaginarium of Doctor Parnassus.”

A gaggle of reporters gathered outside a New York City funeral home Thursday in search of news about Ledger’s funeral. A long line of celebrity deaths have been handled by the same funeral home over the last century, from Judy Garland, John Lennon and Notorious B.I.G. to Jacqueline Kennedy Onassis and Leona Helmsley.

George Amado, general manager of the Frank E. Campbell funeral home, refused to disclose details about Ledger’s funeral arrangements, saying that any additional information would have to come from Ledger’s manager.

An Australian newspaper reported Friday that Ledger would likely be buried in his hometown of Perth, in western Australia, after a star-studded funeral service in Los Angeles. Australian model Sophie Ward said she was planning to fly to the United States on Friday for Ledger’s funeral service.

“I think we’re going to L.A.,” Ward told The West Australian newspaper for its Friday edition. “This is just a funeral service. He’ll probably be buried in Perth.”

The Associated Press contributed to this report.