Massive tree branch falls at San Antonio Zoo, injuring seven guests.

A large tree branch fell on the spring break crowds at the San Antonio Zoo, injuring seven people, including a child who remained in serious condition on Thursday. Visitors rushed to help those pinned under the branch, and dramatic video recorded the ensuing chaos. The zoo is investigating the cause of the breakage to prevent this unusual event from happening again. An arborist theorized the tree may have been overweight and may have had some decay in the union.