A 20-year-old Mazda Motor Corp. worker was arrested Saturday for allegedly killing a colleague at a company dormitory in Hiroshima and robbing him of cash, police said.

Suguru Kamikawa is suspected of beating Kyohei Sugano, 19, to death with a fire extinguisher in an emergency stairwell at around 3:35 p.m. on Sept. 14 and robbing him of some ¥1.2 million ($11,900) that he had withdrawn from an automated teller machine earlier in the day, police said.

Kamikawa admitted to the charge and told investigators he had become angry at the victim while they had been talking.

Both Kamikawa and Sugano joined the automaker in April last year and lived on the same floor of the dormitory in the city.

Kamikawa returned to work after the murder, police said.