"My thoughts are with his family during this very difficult time," says Olsen
Credit: Jeff Vespa/WireImage; Cliff Lipson/Showtime

Mary-Kate Olsen spoke out Friday for the first time since Heath Ledger‘s death earlier this week.

“Heath was a friend. His death is a tragic loss. My thoughts are with his family during this very difficult time,” Olsen said in a statement released through her rep to PEOPLE.

Olsen was one of the first people to be alerted about the actor’s death, when the masseuse who discovered Ledger’s body on Tuesday called the actress.

Starting at 3:17 p.m. Tuesday masseuse Diana Wolozin spent nine minutes making three phone calls to Olsen – and waiting more than a minute between each call – before dialing 911, then called Olsen a fourth time after paramedics arrived at Ledger’s New York apartment, the Associated Press has reported.

Wolozin, 40, used Ledger’s phone to speed-dial Olsen after she shook him to tried to wake him up and found that he was unresponsive. Olsen told the masseuse she would call security people in New York for help, but the masseuse called Olsen back to say she would call 911 herself, sources say.

Police have said they will not question Olsen in connection with the phone calls.

Ledger, 28, and Olsen, 21, first met in the summer of 2006 and “were casually dating” before the actor’s death, according to a source.