A man forced his way into a house armed with a device minutes before an explosion which killed both him and his ex-partner, with the woman's death being treated as a homicide, police said.
Officers were called to a "domestic-related incident" in Sternourt Road, Bristol, at 6.17am on Sunday.
At around 6.30am, police were told a man was believed to have an explosive device at the property, then around two minutes later an explosion occurred.
Police named 35-year-old Jo Shaw and her 41-year-old former partner, Ryan Kelly, who both suffered fatal injuries.
Three other people, including a child, were treated for minor injuries.
Superintendent Matt Ebbs, investigating, said: "Jo's death has been officially recorded as a homicide based on the information known to us at this time. We are not looking for anyone else in connection with her death."
Avon and Somerset Police said a referral would be made to the Independent Office for Police Conduct due to previously reported domestic-related incidents.
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Officers worked with the city council to evacuate people staying in neighbouring properties as a precaution, and a temporary rest centre was set up.
Police said extensive searches were carried out by the army's explosive ordnance disposal team and specialist police officers to ensure the area was safe.
The cordon was reduced on Sunday night, and almost all residents were allowed to return home.
A search of an address in Speedwell linked to Mr Kelly concluded over the bank holiday weekend, with no evacuations required at that location, the force added.
Supt Ebbs said: "Police activity continues to be carried out at the property in Sterncourt Road and we expect this will take several days to be completed.
"We would like to reassure the public there is not believed to be any wider risk to safety and this is not being treated as terrorism-related.
"As previously stated, we believe the cause of the explosion to be deliberate. Analysis work of the explosive device has not yet been completed."
(c) Sky News 2026: Woman, 35, killed in Bristol house explosion after ex-partner 'forced entry'
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