Police said on Saturday they had arrested a married couple on suspicion of murder, following the death of a three-month-old baby boy in the early hours of the morning.

The suspects are a 35-year-old man and his 24-year-old wife.

Officers said they had received a report from the male suspect at 1:54 am about a baby being found unconscious at a flat in Peony House West Block in Tai Kok Tsui.

The infant was rushed to Kwong Wah Hospital and later certified dead shortly after 3 am.

Acting assistant district commander Chiu Ping-fai said the baby showed signs of injury.

"We found a number of suspicious injuries on the baby. The pathologist has examined the baby and found that there were some wounds on the right [side of the] face near the eye corner, and some burn wounds on the baby's left forearm, left leg, right thigh and right foot,” Chiu said.

“One of the lines of investigation is that there may be child abuse or neglect."

He also said officers had contacted the infant's biological mother, who has financial difficulties and had entrusted the arrested couple to take care of the baby since late July.

Chiu added that the couple themselves have a nine-month-old boy, who was unharmed.