The explanation came after a second day of angry protests outside US diplomatic buildings in China.

Nato's raids on Yugoslavia continued on Saturday night, but the capital was not reported to have been attacked.

The US said faulty information led to an initial intelligence mistake which was never corrected.

A joint statement from the US Defence Secretary, William Cohen, and the CIA director, George Tenet, said the incident was an anomaly unlikely to occur again.

BBC Defence Correspondent Jonathan Marcus says the Pentagon is not expected to offer further explanation of its error, for fear of revealing too much about the process used for selecting targets.

Angry demonstrations

Jill McGivering: Demonstrators call for "blood for blood"

Sunday saw a second day of angry demonstrations against the embassy attack, with protesters gathering outside US diplomatic buildings in several Chinese cities.

Chinese residents of Belgrade also staged a protest outside the bomb-damaged embassy building.

The Chinese authorities backed the protests, saying they fully reflected the anger of the people.

Demonstrations in China had the government's approval

BBC Beijing Correspondent Duncan Hewitt said the authorities even seemed to be encouraging the demonstrations.

Students were bussed in from university campuses, and the mood was fanned by angry comments in the morning papers.

The official People's Daily newspaper implied that the bombing had been no accident, and said Nato was accountable for spilling Chinese blood.

Beijing Correspondent Duncan Hewitt: "This is not about to suddenly die down"

However, the authorities vowed to protect foreign diplomats on its soil after protesters on Saturday threw stones at US and UK buildings.

The residence of the US Consul General in the south-western city of Chengdu was stormed and partially burned.

(Click here to see a map of Saturday night's bombing)

More bombing raids

Calls for an end to Nato's air campaign appeared to have little effect on alliance chiefs.

Serbian state radio said overnight attacks on relay transmitters put state and private television and radio off the air in a number of areas.

A post office at Uzice - south of Belgrade - was also reported to have been destroyed, cutting off local telephone links.

Other targets included a piping factory in Valjevo, which Nato said made munitions.

Journalists killed

Kevin Connelly: Nato's highly visable mistakes undermine their attempts to shape public opinion"

The hit on the Chinese embassy on Friday night killed at least three people - a female reporter for China's state news agency, Xinhua, another journalist and his wife.

US President Bill Clinton expressed deep regret for the embassy strike, but said it had been an accident, not a barbaric act.

He echoed the words of Nato Secretary-General, Javier Solana, saying the incident would not deter the alliance from continuing its air campaign.

Correspondents say the attack will make it harder to avoid China's veto during any peace talks at the United Nations Security Council.

Diplomatic track continues

Diplomacy continues: Ibrahim Rugova meets Gerhard Schröder

As the political fallout continued, Russia's special Balkans envoy, Viktor Chernomyrdin, said the conflict had to be resolved by political means as quickly as possible.

He was speaking after talks in Bonn with the German Chancellor, Gerhard Schröder, about the G8 countries' peace plan for Kosovo.

Both men held separate talks with Kosovo Albanian leader Ibrahim Rugova.

Mr Chernomyrdin said that following his talks he was expecting to return to Moscow and not to Belgrade as had previously been suggested.

• Picture gallery: Fury at embassy bombing
• UN moves to ease refugee burden
• Calls to investigate Agani killing
• Embassy bombing dominates Serb media
• The Chinese embassy strike in quotes

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