The death of a one-year-old boy at a nursery is being treated as “suspicious” by police, with six women arrested in connection with the incident.

West Midlands Police said a criminal investigation was launched after the boy’s death on December 9 and a subsequent Ofsted inspection.

The nursery, in Bourne Street, Dudley, has since been shut down by the education watchdog.

The force said three women – aged 20, 23 and 50 – were arrested on December 16 on suspicion of gross negligence manslaughter and later bailed.

Three more women – aged 51, 53 and 37 – were detained on Wednesday, two on suspicion of corporate manslaughter and one on suspicion of gross negligence manslaughter.

In a statement, police said: “We are treating the death of a one-year-old boy on 9 December at a Dudley nursery as suspicious and an investigation is under way.

“The boy’s family is being supported by specially trained officers.

“A post-mortem has taken place but further tests will be conducted to establish the exact cause of death.”