A police cordon is in place and forensics teams are investigating at two separate locations in Middlesbrough on Wednesday (September 20) morning.
Several police vehicles were spotted at South Terrace in South Bank overnight, which saw several properties sealed off.
Police officers and specialist forensics teams are still on the scene, and the properties remain cordoned off at this time.
Read more: LIVE: Cordon in place and forensics in place at South Terrace and Ajax Way in Middlesbrough
A separate investigation is also taking place at a block of flats on nearby Ajax Way in South Bank.
It's unknown at this time whether the two incidents are linked.
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Images from the scene show forensics teams combing the scene of both properties, while a large police presence remains at both houses.
The Northern Echo has contacted Cleveland Police for more information about the incident.
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