Initially peaceful, the protests took a violent turn when the team negotiating on behalf of the Poznan strikers were detained in Warsaw. The demonstrators stormed Poznan prison, liberating 257 inmates, destroying records, and seizing armaments. These insurgents marched back to the city centre to continue their protests. The communist authorities reacted by deploying thousands of soldiers plus hundreds of tanks and armoured personnel carriers. Street battles followed, but with the city cut off from the outside world so that the protesters couldn’t receive reinforcements, order was restored by 30th June. Officially, the clashes left 76 civilians and eight soldiers dead, with over 600 strikers injured. Unofficial estimates were higher. The victims included a thirteen year old boy, Romek Strzalkowski, who was shot dead whilst waving a Polish flag. News of the riots sparked an equally heroic anti-communist uprising in Budapest later in the same year, also brutally suppressed.