LONDON (AP) - British police say they are searching for a woman who gave a baby a bottle believed to contain bleach.

The Metropolitan Police force says an 11-month-old boy vomited Thursday after drinking from "a baby bottle with an unknown substance" given to him by an unknown woman as he sat with his mother and grandmother at a McDonald's restaurant in southeast London.

The force says the boy was taken to a hospital for observation. He is in stable condition. Police say they are examining security footage to see exactly what happened.

Earlier Thursday the police force tweeted: "WARNING! Last 1/2 hr. (hash)Eltham High St. White female in 50s giving children in pushchairs bottles containing believed bleach."

Police say no arrests have been made.

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