A German court has found former SS lieutenant who is top of a most-wanted list of Nazis, Gerhard Sommer, unfit for trial.

Mr Sommer, 93, is thought to have played a role in the mass murder of 560 civilians in an Italian village during World War II.

Prosecutors in Hamburg said on Thursday that his dementia was too severe for him to stand trial, Deutsche Welle reported. He is top of the Simon Wiesenthal list of most-wanted Nazis.

If he were to have stood trial he would “with high probability have been charged with 342 cases of murder, committed cruelly and on base motives,” said prosecutors. They added that his dementia would make him a passive “object of prosecution.”

Mr Sommer now lives in a nursing home. But on August 12, 1944 he was one of 10 SS-soldiers accused of surrounding the village of Sant-Anna di Stazzema, in Tuscany and massacring hundreds.

Victims were shot, beaten and burnt alive by Nazis bearing flame throwers and machine guns retreating up north ahead of the Allied troops.

Women and children were made to kneel and pray in front of the church before being shot, said the Bild newspaper.

Italian prosecutors found Mr Sommer and nine others guilty in absentia in 2005 and sentenced them all to life in prison but Germany never extradited them. They were all members of the 16th SS Panzer division.

A court in Stuttgart found in 2012 after a 10-year investigation that there was not enough evidence to hold them personally responsible, according to Deutsche Welle.

Hamburg lawyer Gabriele Heinecke represented the victims’ families and told the taz newspaper in an interview that she was disappointed with the way the prosecution came to its decision and that dementia was something regularly faked.

“When it comes to pensions, it’s something that happens every day,” said Ms Heinecke.