Indonesia made final preparations on Tuesday to execute eight foreigners by firing squad, as family members wailed in grief during final visits with their loved ones, and ambulances carrying white coffins arrived at the prison.

Relatives of Myuran Sukumaran and Andrew Chan, the Australian ringleaders of the so-called Bali Nine heroin trafficking group, arrived at the Nusakambangan island prison and pleaded for mercy. Sukumaran's sister collapsed in grief.

They are among nine prisoners, including nationals from Brazil, the Philippines, Nigeria and Indonesia, who are facing imminent execution after authorities gave them their final notice.