barcelona protesters clash police try reclaim dispute religious artefacts museum catalonia monday late display tension catalan separatists spain central government ahead dec. 21 election monastery neighbor aragon region say 44 artefacts sell illegally catalonia 1980s issue become symbol broad disagreement opponents supporters catalan independence culture minister inigo mendez de vigo anger catalan nationalists november use special temporary power accept petition judge aragon call artefacts return previous home monastery sijena previous month madrid take control catalonia quell crisis secession call snap regional election hundreds demonstrators monday mass museum lleida western catalonia artefacts keep pro-independence group call supporters stop police remove minor scuffle though injuries report artefacts eventually take away around noon former catalan leader carles puigdemont currently self-imposed exile brussels criticise move twitter blame three principal unionist party run upcoming elections rule people party pp socialist party ciudadanos carry night use militarise police force always take advantage coup etat plunder catalonia complete impunity model ciudadanos psc pp defend puigdemont say prime minister mariano rajoy say government could oppose court rule would mean step outside rule law catalan protesters clash police 'plunder religious artefacts