Supporters of the left-wing Zapatista rebels have staged demonstrations across Mexico City, blocking access to the main stock exchange and occupying two radio stations. The protestors demanded that the government dismantle paramilitary groups believed to be responsible for the killing of 45 indian peasants almost two weeks ago. As our Mexico correspondent, Emma Paterson, reports, the demonstrations are another sign of the increasingly tense stand-off between the government and rebels, who took up arms more than four years ago.

Mexico City has been the focus of a co-ordinated spate of protests carried out by rebel sympathisers. Demonstrators stormed two radio stations, demanding that a taped message from the Zapatistas be broadcast on the airwaves.

Security forces eventually moved in to end the three-hour occupation. The country's stock exchange was another target, as protestors blocked the entrance to the building for more than half an hour, delaying the start of trading.

Well-dressed financiers looked on in silence, as the Zapatista sympathisers laid coffins outside the building in memory of the 45 indian peasants killed in last month's massacre in the Southern state of Chiapas. The demonstrators said pro-government paramilitaries had been responsible for the attack and called for the resignation of the state governor.

The stock exchange blockade was a publicity ploy, clearly intended to shake the confidence of foreign investors. Propaganda is now the most powerful weapon which the militarily-weak guerrilla force is able to wield.

The rebel aim is to keep international attention focused on the conflict in Chiapas and to embarrass the government into accepting their terms for the resumption of peace talks. The negotiations broke down more than a year ago, after the government rejected a key rebel demand concerning partial autonomy for indian communities.