Pakistan moved thousands of troops away from its border with Afghanistan towards its Indian frontier yesterday, marking a big increase in tensions between the nuclear-armed neighbours after the Mumbai terror attacks.

The move of 20,000 troops – the army’s 14th Division was being redeployed to Kasur and Sialkot, close to the Indian border – struck a blow against attempts to thwart al-Qaeda and Taleban extremists along the Afghan border. All troop leave has also been cancelled.

Manmohan Singh, the Indian Prime Minister, met the chiefs of his army, navy and air force to discuss “the prevailing security situation,” according to an official statement.

India blames Pakistan-based militants for the attacks last month on Mumbai. Both countries rushed troops to the Kashmir region after the attacks but tensions cooled after intensive international diplomacy.

Pakistan has deployed more than 100,000 soldiers in Waziristan and other northwestern regions to fight Islamic militants blamed for surging violence against British and US troops in Afghanistan. The Government also blamed militants in the tribal region for masterminding the assassination of the former Prime Minister Benazir Bhutto a year ago.

Little progress has been made in finding those who plotted the assassination. The Pakistan authorities’ investigation has ground to a halt and police have been ordered not to speak about the case.

The ruling Pakistan People’s Party (PPP) is divided over its handling of the murder. Many leading party members accuse her widower, President Zardari, of suppressing the investigation. “It is intriguing why the Government has not even ordered any investigation into Ms Bhutto’s killing,” said Safdar Abbasi, a senator.

Initial investigations under the government of the former President Musharraf blamed a Taleban commander, Baitullah Mehsud, for the assassination. It also invited Scotland Yard to conduct a forensic investigation. The trail has gone cold since the new government halted the investigation.

General Hamid Nawaz, a former Interior Minister, said that Mr Zardari did not allow a postmortem examination to be conducted on his wife, further complicating the investigation.

Farhatullah Babar, a spokesman for Mr Zardari, confirmed that the Government was not conducting an investigation. “We do not want to appear witch-hunting,” he said.

However Pakistan has asked the United Nations to conduct an inquiry – which last night Ban Ki Moon, the UN Secretary-General, said was likely to go ahead. In a statement he said he hoped that an inquiry would be set up “in the near future”.

Mr Zardari has said that there could be a possibility of the involvement of some other country but he has never elaborated. He was elected President in August, replacing Mr Musharraf, who ruled for eight years.

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