A man was arrested Monday on suspicion of murdering his colleague, by dumping heavy construction materials on him using a forklift truck at a construction company in Oita Prefecture, police said.

Hideyuki Suemitsu, 38, has admitted to killing Takashi Fujita, 53, around 9 a.m. Saturday at the company's storage yard, according to the police.

Investigators are looking into possible difficulties between the two, the police said, adding that Suemitsu is suspected of dumping wall material weighing about 2 tons on Fujita.

The two were transferring materials out of the yard at the time. Suemitsu was said to have left the scene shortly after the incident, in order to move the material he is suspected to have used in the murder to a construction site.

A pedestrian passing by the yard saw Fujita bleeding from his head on Saturday morning.