Austrian prosecutors say the woman sent the American actor more than 100 letters, pursued him for an autograph and then sent death threats when he refused to give her one.
She was charged with stalking and threatening to kill Caruso, but failed to show up for court in 2007 and was believed to be on the run.
Tijuana police said Friday they detained the woman with the help of a blog titled The Stalker Chronicles, dedicated to the woman's arrest. She was turned over to immigration officials late Thursday and will likely be deported.
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