 However , by April 1935 the fragile truce between pro @-@ open shop management and pro @-@ union forces broke . A long , violent strike ensued . <unk> were hired , and within four days the company rolled out heavily fortified streetcars , complete with windows covered by heavy wire and armed guards on board . While few cars attracted passengers , the cars encountered little resistance . The company resisted calls for arbitration from the Omaha City Council , and continued employing <unk> . In early May violence broke out , with rifle attacks , violent <unk> and bombings across the city . In June riots broke out throughout the city with <unk> burning streetcars , looting and two deaths . The city government lost control of the violence and called in the National Guard , which sent 1 @,@ 800 troops while Governor Robert <unk> declared martial law and ordered the streetcars to stop running . After the governor intervened and Wattles allowed arbitration , a number of agreements were made . However , no changes occurred , and <unk> stayed on the job . The violence ended , court cases ensued , and the situation slowly faded away . The Omaha Traction Company never <unk> . 
