President Clinton has expressed outrage after an abortion doctor was killed by a rifle shot through the window of his home in New York state.

The death comes days after abortion clinic workers in the area and in southern Canada had been warned to take extra care.

The doctor, Barnett Slepian, is the third doctor carrying out abortions to be killed in the last five years.

Mr Clinton said the nation could not tolerate violence directed at those providing a constitutionally-protected medical service.

The BBC New York correspondent says abortion is one of the most divisive issues in the United States.