Polish insurrection in Upper Silesia

[This Document is the Property of His Britannic Majesty's Government, and should be returned to the Foreign Office if not required for official use.] 209 154 C- 9060 POLITICAL. 4 ###21 UPPER SILESIA. Decypher. Colonel Percival (Oppeln) May 3rd, 1921. D. May 3rd, 1921. 12.0 noon. R. May 3rd, 1921. 7.0 p.m. No. 78 (R). MOST URGENT. Polish insurrection broke out last night simultaneously on Eastern border of Industrial area and in Pless Rybnik. Greater part of Beuthen rural Pless and Rybnik districts are now in the hands of rebels. In the latter two Italian troops have been attacked in their barracks, and a number of officers and men killed and wounded. Polish agents have also blown up railway bridges which connect Upper Silesia with Germany. Polish section of Upper Silesian Police has in many places gone over to rebels, after disarming German section. Amongst insurgents there are men in Polish uniforms and six lorries with arms and ammunition crossed the frontier from Poland in Beuthen district. It is clear that we have to do with a concerted Polish plan to seize Upper Silesia by force. I have no evidence that Polish Government has any connection with the movement, but I should be grateful if it could be reminded of its promise to close the frontier. (group undecypherable) Captain Simson, Police Officer at Zaborze, has been taken prisoner by Polish insurgents. Repeated to Paris, Berlin and Warsaw. MAY RECEIVED IN REGISTRY. FOREIGN OFFICE.