Aum Shinrikyo cult founder Shoko Asahara, who was executed Friday for numerous crimes, suffered no psychiatric problems, sources with knowledge of his behavior in a detention facility said.

The 63-year-old, who masterminded the 1995 sarin gas attack in the Tokyo subway system and 29 other murders, had been seen sitting silently without speaking to guards.

However, he was able to stand up on his own when he was told to take a bath, once in several days, at the Tokyo Detention House, the sources said.

Asahara's family had claimed he was mentally incompetent and could not be executed under the law, but multiple Justice Ministry sources denied any abnormality in his mental capacity.

Since mid-2008, Asahara, whose real name was Chizuo Matsumoto, had declined all meeting requests from his family and lawyers.

According to the sources, the cult founder's appearance had completely changed after his arrest when he had his hair cut short and removed his beard.

He spent most of the day sitting in his solitary cell, but did communicate with a doctor who regularly came to check his condition.

Refusing to use the toilet in the cell, he always wore a diaper. He was also sometimes seen with rough skin.

A document submitted by the detention center to the Yokohama Family Court in May 2015, citing a diagnosis by a psychiatrist, said Asahara had "no explicit psychiatric disorders."

The document was submitted in connection with a request made by a daughter of Asahara to nullify her parents' right to inherit her property in the event of her death.

In addition to Asahara, six former senior members of the cult were also executed on Friday. They were among 13 people placed on death row in connection with a string of crimes.