Who petrified muggle-born students in Harry Potter and the Chamber of Secrets?

The petrified muggle-born students in Harry Potter and the Chamber of Secrets were petrified by Tom Riddle, who was using the diary of his younger self to control Ginny Weasley.

Here's a breakdown:

* Tom Riddle (Lord Voldemort) opened the Chamber of Secrets and unleashed a giant basilisk.

* Ginny Weasley, possessed by the diary, wrote in it and was influenced by Tom Riddle's past self.

* The Basilisk was used by Riddle to petrify the muggle-born students, as he believed they were a threat to the wizarding world.

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