One woman is reported to have been killed in Mexico after thousands of demonstrators clashed with police during a national day of protest to condemn the recent massacre of 45 Indian peasants in the southern state of Chiapas. Police in Chiapas are reported to have opened fire on a group of unarmed Indians during one of many demonstrations which have been held across the country. The protests coincided with a government decision to replace its chief negotiator at the peace talks with the left-wing Zapatista rebels who are based in Chiapas. From Mexico City, Emma Paterson reports:

Tens of thousands of Mexicans jammed into the historic centre of the capital in one of the biggest demonstrations of its kind. "Down with the President", "Down with the killers", shouted the crowd, which filled the city's main square and overflowed into surrounding streets.

The protestors fell silent as reports were relayed over the loudspeaker that police had opened fire on fellow demonstrators in the state of Chiapas. One person was said to have been killed and two others injured.

The size of the demonstration in Mexico City was testimony to the widespread sense of shock and anger over the recent killing of 45 unarmed peasants, the majority of them women and children. The protestors, some of them supporters of the Zapatista rebels, accused the state authorities of being involved in the massacre.

Many of the victims were also thought to be rebel sympathisers. The government has denied that the attack was part of an official counter-insurgency strategy and has promised a full inquiry.

A senior police officer has already been charged in connection with the massacre, which has caused a scandal both at home and abroad. Facing growing pressure to end the violence in Chiapas, the government has now appointed a former vice-minister as its new chief negotiator in peace talks with the rebels.