Police believe that a family dispute likely led to the murder of six people whose bodies were found Monday at a home in Miyazaki Prefecture.

The police retrieved a body believed to be that of Masahiro Iihoshi, 42, from a river on Tuesday about 3 kilometers away from the home.

Iihoshi was missing when the bodies of his five family members and a friend were discovered at his residence in the town of Takachiho. Investigators believe he took his own life by jumping from a bridge.

The six have been identified by the police as Iihoshi’s father Yasuo, 72, mother Mihoko, 66, wife Mikiko, 41, son Takumi, 21, daughter Yui, 7, and his friend Fumiaki Matsuoka, 44. Some of the bodies had knife wounds and a bloodstained machete was found at the site, according to the police. Mihoko’s body, the only one to be found outside the house, had sustained serious injuries, they said. TV Asahi and Fuji News Network reported that she had been decapitated.

The bodies of Mikiko and Yui had few visible wounds except for signs they were strangled, according to investigators. The five bodies inside the house were found in different rooms, they said.

It is believed there had been some kind of dispute between Iihoshi and Mikiko.

Matsuoka had said he was going to meet the family to mediate on Sunday, indicating that problems had occurred that day. Matsuoka’s father called the police on Monday morning after being unable to contact his son.

Worried about Yui’s absence from school, the vice principal of Oshikata Elementary School visited Iihoshi’s home Monday morning, but no one answered the doorbell and the front door was locked.

Iihoshi’s brother also contacted the police on Monday, saying he was unable to reach the family by phone. A police officer then visited the home and found the bodies.

On Sunday, Iihoshi attended a year-end party organized by his company, along with his wife and daughter, and parted with colleagues after having lunch, according to the company.

“I still can’t believe this has happened. I want to know the truth behind it,” said a man in his 60s who works near the site.

In Japan in recent years, there have been a series of multiple murders by members of the same families or within small rural communities.

In April this year, a man was arrested on murder charges after his uncle’s wife, her sister and a friend were found dead at a private home in the city of Hioki, Kagoshima Prefecture. Based on his statement, the bodies of his father and grandmother were later found in a nearby forest.

In October 2017, five children aged between three and 11 were killed along with their mother in an apartment in the city of Hitachi, Ibaraki Prefecture. The father was then arrested and indicted on murder charges in February.