A 12-year-old member of an idol group who fell unconscious Saturday after inhaling helium for a television show has not yet come round, TV Asahi said.

The Metropolitan Police Department is questioning staff at TV Asahi and could file charges of professional negligence.

Although she is showing signs of improvement, the girl may be suffering from a cerebral air embolism, in which air enters a blood vessel in the brain, a medical specialist said Wednesday.

The unnamed girl is one of 27 members of idol group 3B junior. She took part in a game involving helium gas, which is sold in stores to make people's voices sound funny at parties, at the TV station's studio in Tokyo.

TV Asahi apologized to the girl and her family and said it delayed announcing the incident because it expected an earlier recovery.