Actor Nick Santino and his dog, Rocco. Personal photo

(CBS) Soap opera actor Nick Santino killed himself last week after putting his pet dog to sleep, according to the New York Post.

The paper reports that the actor put down his beloved 5-year-old pit bull, Rocco, on Tuesday - his 47th birthday - and was found dead the next day of an apparent pill overdose.

Santino, who appeared in roles on "Guiding Light" and "All My Children," reportedly left behind a suicide note in which he said he "betrayed [his] best friend."

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"Rocco trusted me and I failed him," he wrote, according to the Post. "He didn't deserve this."

The actor reportedly put Rocco to sleep following pressure from his apartment building's condo board, which had begun enforcing strict rules about owning dogs - breeds like pit bulls were reportedly banned, and dogs could not ride in the main elevator or be left alone in apartments for more than nine hours.

Although the ban didn't apply to pit bulls already in the building, the Post reports that Santino, who adopted Rocco from a shelter several years ago, received complaints and had been "harassed" by the building's management.

Santino reportedly called a former girlfriend at 2 a.m. on Wednesday and was found dead in his apartment, on New York's Upper West Side, later that day.

On Monday, the actor's sister told the Post that Santino would be buried with the ashes of his beloved pet.

Read the full story at the New York Post.