Lia Toby / WENN 1 / 13
Lia Toby / WENN 1 / 13

Lily Collins and Jamie Campbell Bower have broken up, sources tell Us Weekly exclusively. The actors, both 24, were first romantically linked in July 2012 while shooting "The Mortal Instruments: City of Bones" in Toronto. "They remain very good friends," an insider says.

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In preparation for the supernatural film's Aug. 21 release, the exes have been on a nationwide press tour that included mall appearances, television interviews and more. "They've been really good about doing the press tour together for their movie," a source explains of the professional pair. "They were able to stay friendly."

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Collins previously dated her "Abduction" co-star Taylor Lautner from November 2010 to September 2011; she also romanced Zac Efron for three months in 2012. Campbell Bower, meanwhile, was previously engaged to his "Harry Potter and the Deathly Hallows: Part 1" co-star Bonnie Wright. They quietly split in June 2012 after two years together.

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