Instapaper, the online bookmarking service, said in a blog post Thursday that the FBI illegally took some of its data in an unrelated raid Tuesday night.

The data Instapaper thinks was obtained by the agency includes its user data and the service’s Web site codebase. Other unrelated sites including Pinboard and the Curbed Network were also affected by the server seizure.

The FBI said Wednesday that the raid was intended to crack down on an international “scareware” ring. Scareware is malicious software that poses as antivirus or security software.

DigitalOne, a Switzerland-based company that has a data center in Reston, Va., told the New York Times that the raid was targeting one of its customers but that the agency probably took more servers than it was targeting.

Marco Arment, Instapaper founder, said in a blog post that he believes his data were on one of the servers seized by the FBI.

“I’m assuming this because it became unreachable and stopped sending updates to my internal monitoring system at approximately the time that the FBI raided the datacenter, and has not come online again since then,” he wrote.

Arment said that no user data had been lost and the site suffered no downtime. But the servers he believes were taken do contain e-mail addresses and information on user bookmarks. The servers also had, “salted SHA-1 hashes of passwords,” which he believes should be relatively safe.

The FBI did not immediately comment on the accusations.

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