OLYMPIA, Wash. - Voters have approved a ballot measure making Washington the second U.S. state to allow terminally ill people the option of medically assisted suicide.

The measure, patterned after Oregon's "Death with Dignity" law, allows a terminally ill person to be prescribed lethal medication, which would be self-administered. With about 30 per cent of the expected vote counted Tuesday in unofficial returns, about 58 per cent of voters had approved the measure and about 42 per cent rejected it.

Supporters say the initiative will provide a compassionate way for sick people to die.

Opponents, including the Roman Catholic church, say assisted suicide is a dangerous step that devalues life.