OSAKA -- A 23-year-old man was arrested early Monday for fatally striking his father on the head with a golf club at their apartment in Higashi-Yodogawa Ward here, police said.

When officers rushed to the scene after receiving a call at 1:25 a.m., they found Yasuo Goto, 48, self-employed, collapsed on the floor, police said. A man in the room told police he killed his father.

Goto was pronounced dead about an hour later at a hospital, they said, adding that his wife, Chikako, was also seriously injured.

Police arrested their son, Shuji, at the scene for attempted murder and are now investigating him on suspicion of murder, they said.

Police suspect that the son, a part-time employee at a travel agency, struck his father several times on the head with the club while the victim was asleep.