A US man charged with 11 murders after the remains of 10 bodies and a skull were found in his Ohio home has pleaded not guilty by reason of insanity.

美国俄亥俄州一名男子家中发现10具尸体和一块颅骨，他因此被指控谋杀11人，但是他以精神错乱为名拒绝认罪。

Assistant prosecutor（助理检察官） Rick Bombik told local news media that he thought Anthony Sowell would have a difficult time proving he was insane（精神错乱的）.

"Under Ohio law you have to be able to prove you do not know right from wrong," he said.

If found guilty, Mr Sowell could face the death penalty.

The 50-year-old appeared in court via a video link from prison on Thursday. Judge Eileen Gallagher ordered he be held without bail.

A pre-trial hearing（审前听证） has been set for 7 December.

The former US marine is also charged with kidnapping, rape and abusing a corpse（尸体）, among other indictments（起诉，控告）.

Investigators are examining whether he may also be connected to unsolved killings elsewhere.

On Wednesday, FBI agents carried out a search of a house Mr Sowell had lived at in the 1980s before being sent to prison for 15 years for attempted rape. No bodies were found.

The investigation into Mr Sowell began after a complaint to police by a 36-year-old who said she was attacked by him.

Police found the remains of 10 women on his property and a separate skull. Most of the victims appear to have been poor black women with drug addictions. The coroner said most of them were strangled（勒死，使窒息）.