WALNUT CREEK — Police here are investigating the death of a 1-year-old boy who began choking while playing in the shower, authorities said.

The boy, who this newspaper is not naming, began choking inside the shower of the Desert Circle apartment where he lived with his parents. He went unresponsive on the way to the hospital, and was pronounced dead there, authorities said.

The May 10 incident remains under investigation. The boy’s mother allegedly told police that her son had been playing in the shower and that she checked on him after he stopped making noise.

When she realized he was choking she took him to the hospital, but stopped on the way when he went unconscious. A police officer caught up with them and attempted CPR, then an ambulance took the child to a nearby hospital, authorities said.

Police are arranging tests on a bucket of liquid found near a mop in the bathroom, and seized several other items from the apartment, authorities said. Neither of the boy’s parents have been arrested or charged but police are investigating it as a possible negligence death, court records show.