On the morning of May 7, at least two-dozen demonstrators entered the PYLE Office Building "when the doors were unlocked and planted themselves on the inside stairs that led to the Selective Service Office within the building (see Figure 27). Shortly after 9 [A.M.], [law enforcement personnel] arrived and asked them to leave. The demonstrators refused. Police warned that tear gas would be used if necessary. Efforts by officials from the Dean of Students Office, [including C. ARTHUR SANDEEN, Dean of Students] failed to persuade the group to disperse. 

At this point, police evacuated the building and a tear gas canister was released in the lobby" (Swan, 1998, p. 23). "As the canister’s contents did their work, demonstrators ‘came stumbling and coughing out into the bright sunshine’" (Swan, 1998, p. 25). (see Figures 28 and  29). The tear canister was later carried out by Jim Hannah, a former student and head of the ISU Draft Counseling Center (Gilbert, 1970, May 8, p. 1) (see Figure 30).

Figure 28.

Figure 29. 

Figures 28 and 29.  Protestors exiting the PYLE Office Building after a tear gas canister was released in its lobby.

Figure 30.  Cloud from a tear gas canister outside the PYLE Office Building. 

"But the struggle was far from over. Some of the gassed demonstrators flopped to the ground and resisted arrest. Mace and blackjacks were used by … [law enforcement officials] to hand-cuff and arrest 23 demonstrators" (Swan, 1998, p. 25) (see Figure 31).