Four nurses aides were convicted Friday and sentenced to terms ranging from 15 years to life in the deaths of at least 20 elderly patients killed by drug overdoses or by forcing water into their lungs.

The four, dubbed "The Angels of Death" in Austria's newspapers, initially admitted to being involved in the deaths of 42 old and chronically ailing patients at Vienna's Lainz Hospital between 1983 and 1989. They later retracted most of their confessions.A three-judge panel sentenced Waltraud Wagner, 32, and Irene Leidolf, 29, to life in prison for murder. Stefanija Mayer, 51, received a 20-year term on attempted murder and manslaughter charges. Maria Gruber, 29, drew 15 years for attempted murder.

Wagner, who appeared in a daze through most of the four-week trial, slumped over as sentence was pronounced. She was given first aid. The jury of six women and two men found her guilty of 15 murders, 17 attempted murders and two cases of aggravated assault.

Mayer collapsed after her conviction for seven attempted murders and one case of manslaughter. She was taken from the courtroom on a stretcher.

Leidorf was convicted of five murders and two attempted murders, and Gruber of two attempted murders.