Former Pakistani military ruler Pervez Musharraf was taken to hospital with chest pains on Wednesday while on his way to face treason charges in a special court in the capital, Islamabad.
It was the third time that Mr Musharraf has failed to appear in court to face the charges. The first two times he cited security concerns.
Mr Musharraf (70), seized power in a 1999 military coup when he was army chief. He later became president and ruled until 2008.
The treason charges relate to his imposition of a state of emergency in 2007, when he was manoeuvring to extend his rule in the face of growing opposition from the public and the judiciary.
Mr Musharraf’s lawyers say he does not recognise the jurisdiction of the court and accuses it of bias.
A spokeswoman for Mr Musharraf said he had been taken to a military hospital in the city of Rawalpindi, near Islamabad.
The case is being closely watched for any impact on the relationship between Pakistan’s three power centres - the military, an increasingly assertive judiciary and the fledgling civilian government.
There is concern that the trial of the former military leader could anger the army, which has ruled Pakistan for more than half its history since independence in 1947.
Mr Musharraf recently told reporters the whole army supported him though the military leadership has given no indication that it might intervene in the trial.
Judge Faisal Arab has said he did not wish to issue an arrest warrant for Musharraf, but may be forced to if he does not appear in court.
Reuters