After the defeat of Wrangel, the Red Army immediately repudiated its 1920 treaty of alliance with Nestor Makhno and attacked the anarchist Black Army; the campaign to liquidate Makhno and the Ukrainian anarchists began with an attempted assassination of Makhno by Cheka agents. Anger at continued repression by the Bolshevik Communist government and at its liberal use of the Cheka to put down anarchist elements led to a naval mutiny at Kronstadt in March 1921, followed by peasant revolts. Red Army attacks on the anarchist forces and their sympathisers increased in ferocity throughout 1921.