Military equipment and weapons made in China are being used against civilians in Darfur in violation of a United Nations arms embargo in the troubled region of Sudan.

One Chinese-built army truck is understood to have taken part in an attack on a village. And Chinese-built and maintained fighter jets are also being used to bomb and strafe civilians, it is claimed.

The findings, in a Panorama documentary to be shown tomorrow, come just four weeks before the start of the Beijing Olympics and amid intense international pressure over China’s close economic, diplomatic and military ties with oil-rich Sudan, as well as its human rights record in Tibet.

Air raiders: Chinese Fantan jets have been used in Darfur, where two million people are homeless 

Film director Steven Spielberg resigned as an artistic adviser to the Games in February over Beijing’s support of the Sudanese government. And actress Mia Farrow, a UN goodwill ambassador, has also sought to draw attention to the two countries’ relationship, calling the Games the ‘Genocide Olympics’.

A UN embargo, in place since March 2005, bans the supply of arms for use in the conflict in Darfur but weapons can still be sold to the Sudanese government for other uses – even though the regime is understood to supply and support the Arab Janjaweed militias blamed for most of the carnage that has cost an estimated 300,000 lives.

Under the terms of the embargo, China has to ‘take measures’ to stop its military hardware ending up in Darfur, but Panorama has discovered some of it is being used there.

Technically, China may not be in breach of the embargo because it has urged the Sudanese government not to allow the equipment to go to the region. However, questions will be asked after Panorama uncovered evidence that new weapons have reached Darfur.

UN experts say two military trucks taken from the Janjaweed by rebels in a remote area of Darfur hold the key to China’s involvement. Serial numbers on the trucks, made by Chinese vehicle manufacturer Dong Feng, matched those of a shipment that UN officials tracked to Sudan after the embargo came into force but were later lost.

International lawyer Clare da Silva told Panorama: ‘The transfer happened after the embargo was in place in 2005 and it’s clear that the Chinese have not taken any measures to ensure that their equipment is not moved to Darfur or used for serious violations of human rights.’

Innocents: The victims of Darfur

People from the village of Sirba in western Darfur said one of these trucks, mounted with Chinese-made guns, was used in a ferocious attack on their homes by Janjaweed militias searching for rebel fighters.

One eyewitness said: ‘We saw a Dong Feng truck. It started firing. The people were screaming. The firing carried on until the houses were burning.’

The Darfur conflict began in 2003 when rebel groups started attacking government targets, complaining that their region was being neglected by Khartoum and that the government was oppressing black Africans in favour of Sudanese Arabs.

The government’s response was to arm and mobilise the Janjaweed militias against them, and the resulting years of violence have led to two million people being displaced from their homes.

It is widely suspected China is Sudan’s main arms supplier. A military parade in Khartoum two weeks ago showed government forces armed with Chinese T-96 tanks, T-92 armoured personnel carriers and surface-to-air missiles.

Panorama has also obtained a photograph of a Chinese-built A5 Fantan ground-attack jet. It had a bomb ready for loading nearby at a base in Darfur. Civilian refugees in Darfur reported being attacked last February by jets.

A Chinese government spokesman in London said last night: ‘There is an arms embargo on Darfur, not on Sudan. We have a normal arms trade with Sudan, like many other countries, and this does not break the arms embargo.

‘I am not in a position to confirm whether the militias have these Chinese-made weapons. But if they do, it does not mean that China has provided them.’

* Panorama, BBC1, 8.30pm tomorrow.