According to "Shoku Nihongi" (Chronicle of Japan Continued), when he was playing Igo (board game of capturing territory), their conversation turned to about Prince Nagaya, and this made OTOMO no Komushi who was given benefits by Prince Nagaya angry, and he was killed by Komushi.
『続日本紀』によると、長屋王に恩遇を受けていた子虫により、囲碁のときに長屋王のことに及んで憤慨して殺されたとなっている。