World highlights

• At least 18 people were killed in gang attacks on buses and police posts in Rio de Janeiro, a state official said, as the Brazilian city fills up with tourists for New Year celebrations. Seven of the people were burned to death on a bus and nearly two dozen were wounded in the violence, which was similar to a wave of bloodshed that hit the business capital Sao Paulo earlier this year on orders from a powerful prison-based gang.

• John Edwards, the Democratic vice presidential nominee in 2004, launched a run for the presidency with a call to cut US troops in Iraq, reduce global warming and end poverty in America. To drive home his populist message, Mr Edwards opened his campaign among the debris and wreckage of New Orleans' lower Ninth Ward, which was wiped out in Hurricane Katrina last year and where the storm's mostly poor victims are still struggling to rebuild.

• Palestinian President Mahmoud Abbas denied reports that his security forces in the Gaza Strip had received an arms shipment meant to bolster him against Hamas rivals. Abbas spokesman Nabil Abu Rdainah denied comments made to Reuters by Israeli security sources, which said the arms shipment had arrived via Egypt.

• Italian Interior Minister Giuliano Amato, a former Prime Minister, underwent heart surgery yesterday but will be able to return to work within 48 hours, a government spokesman said. Mr Amato, 68, is expected to be discharged from hospital today after the coronary angioplasty operation, the spokesman said. Mr Amato served as Prime Minister in 1992-93 and also briefly in 2001.

• A freight train smashed into a bus as it crossed a railway track outside Mexico City yesterday, killing at least 21 people and injuring another nine, local officials said. The bus carrying 30 people drove into the path of the 36-car freight train as it headed north on a highway.