This probe was entirely bespoke.

Federal investigators in Philadelphia used twee shopping site Etsy and a host of social media platforms, including Instagram and Vimeo, to nab a massage therapist accused of torching a cop car, according to a federal complaint.

The suspect, 33-year-old Lore-Elisabeth Blumenthal, was identified by FBI agents who examined footage of a May 30 George Floyd protest and noticed her distinct forearm tattoo and a political T-shirt she was wearing when she allegedly set the police cruiser ablaze.

This photo from federal prosecutors shows protesters damaging a Philadelphia police car.

The T-shirt — which had the phrase “Keep the Immigrants Deport the Racists” emblazoned on it — led investigators to an Etsy page that was selling the custom-made shirts.

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The investigators noticed a review on the page written by a username they later determined was linked to someone named Lore-Elisabeth in Philadelphia, according to the complaint.

They then searched the name on LinkedIn, which turned up a hit for a woman employed as a massage therapist in the city. On the company’s website, videos show a woman giving massages with a peace-sign forearm tattoo that matched Blumenthal’s.

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The website listed a phone number for Blumenthal, which federal authorities used to track down her address in the Germantown section of the city.

She was arrested Tuesday and prosecutors are seeking to detain her until trial, the Philadelphia Inquirer reported.

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