Cambridgeshire police said on Thursday that a boy about 3 years old was thrown into a camel enclosure. He was taken to Addenbrooke's Hospital in Cambridge and is in critical but stable condition.
Police arrested a 30-year-old man from Norfolk on suspicion of attempted murder. Investigators said they do not believe the suspect and the child knew each other. Officers are also trying to determine whether the boy was attacked by the animals in the enclosure.
Detective Chief Inspector Vicky McCann said investigators are speaking with people who were at the zoo at the time to understand what happened. She added that police are supporting the boy's family at the hospital.
British MP Ben Obese-Jecty said his thoughts are with the child and his family during a "particularly traumatic and difficult time," and urged the public not to speculate online. He said he is in contact with senior officers handling what police are calling a "critical incident."