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Thor actress Jaimie Alexander has revealed she sustained "a pretty horrible injury" while filming on the London set for next year's Thor: The Dark World.

Alexander -- who plays Thor's (Chris Hemsworth's) warrior goddess sidekick Sif -- addressed the incident Monday on Twitter. "Today I sustained a pretty horrible injury. I'm lucky I'm not paralyzed. Thank you (with all of my heart) to those who've looked after me."

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The star did not provide more details about the injury, but later posted several updates stating that she was well on her way to recovery. "Already in recovery mode and my spirits are high. I'll be back kicking ass as Lady Sif in no time! It can only get better from here on out!"

Her most recent tweet on Tuesday added: "Received great news today! Meds are kicking in. Awesome funny nurses here at the hospital. Physio tomorrow. All good."

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