Experts have examined photos and videos of the deadly Seattle crane collapse that killed four people. Based on their examinations, the experts believe tower bolts or pins were removed early during dismantling and gusty winds knocked it down.
The Washington State Department of Labor and Industry (L&I) investigation is still ongoing, and no definitive conclusions have been determined.
L&I is investigating at least five companies potentially involved in the April crane collapse.
A similar disaster happened in Dallas in 2012.