Japan on Friday carried out executions of two death row prisoners, including the nation's first of a condemned inmate sentenced by jurors, officials said, as campaigners called for the country to abolish capital punishment.

The two executions for multiple murders bring to 14 the total number of death sentences carried out since Prime Minister Shinzo Abe took power in late 2012.

Sumitoshi Tsuda, 63, was hanged for killing three people in the city of Kawasaki, near Tokyo, in May 2009, a justice ministry official said.

It was Japan's first execution of a death row inmate sentenced by so-called lay judges, the ministry confirmed.

Japan in 2009 launched a jury system in which citizens deliberate with professional judges in a bid to boost the role of the citizenry in the judicial process.

Under the system, a total of 26 people have been sentenced to death, according to public broadcaster NHK.

"Lay judges made the very grave judgement and I took it seriously," Justice Minister Mitsuhide Iwaki told a news conference.

The news made the front pages of Japanese evening papers, with the top-selling Yomiuri Shimbun saying that consideration for the psychological well being of jurors is necessary.

Japanese courts "should give more attentive care" to lay judges who face "psychological burdens" over handing out such sentences, the paper said.

Separately, Kazuyuki Wakabayashi was executed for killing two people -- a 52-year-old woman and her daughter -- in 2006 in Iwate, northern Japan, the ministry official said. The 39-year-old was sentenced to death by professional judges.

Japan and the United States are the only major advanced industrial nations that continue to have capital punishment.

The latest executions prompted angry reaction from international campaigners, who again called on Japan to abolish the death penalty.

They say Japan's system is cruel because inmates can wait years for their executions in solitary confinement and are only told of their impending death a few hours ahead of time.

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"The Japanese authorities' willingness to put people to death is chilling and must end now before more lives are lost," Roseann Rife, East Asia Research Director at Amnesty International, said in a statement.

"The death penalty is not justice or an answer to tackling crime, it is a cruel form of punishment that flies in the face of respect for life," she said.

"Japan should immediately introduce an official moratorium on executions as a first step towards abolition of the death penalty."

Surveys, however, have shown the death penalty has overwhelming public support in Japan, despite repeated protests from European governments and human rights groups.

Japan now has 127 inmates on death row, according to the justice ministry.