(CNN) -- The funeral service for "Sopranos" actor James Gandolfini will be held Thursday in Manhattan, a family friend told CNN on Sunday. 

Gandolfini, who was on a working vacation in Rome, died Wednesday. An autopsy determined his death was the result of a heart attack, according to Michael Kobold, the family friend. 

The actor's remains are scheduled to leave Rome on Monday and arrive in the United States the same evening, Kobold said. The service will be held at 10 a.m. Thursday at the Cathedral Church of St. John the Divine in Manhattan. 

"On behalf of the Gandolfini family, I would like to thank the Italian authorities for all of the assistance they have rendered in expediting the formalities necessary to repatriate James Gandolfini's remains to the United States," Kobold said. 

"We are fully aware that this process usually takes seven days and we are extremely grateful for their efficiency in dealing with this matter. We sincerely thank you." 

The 51-year-old actor arrived in Rome with his son, Michael Gandolfini, a day before he died. 

"Jim was happy, he was healthy, he was doing really fine," Kobold said. "He was on vacation with his son. He has an 8-month-old daughter. Everything was going great. I just spoke to him on Father's Day." 

The same day Gandolfini died, he had visited the Vatican and dined with his son, the family said. 

After he returned to his room, his son alerted hotel staff that he was not answering knocks on the bathroom door. 
Who was he with?
his son