Who killed Howard and Maria Stark?

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Tags

1. #impact
2. #stark
3. #under
4. #december
5. #hydra
6. #killing
7. #causing
8. #after
9. #crash
10. #deaths
11. #cause
12. #initial
13. #while
14. #starks
15. #caused
16. #howard
17. #winter
18. #survived
19. #soldier
20. #maria
21. #control