A woman was bitten by a Staffordshire bull terrier-type dog as she walked home in the early hours.
The victim suffered a bite to the stomach after coming across two "Staffy-type dogs" being walked by a woman aged in her 50s, said Suffolk Police.
The attack happened in South Avenue in Sudbury, at about 3.30am on Saturday.
Police are appealing for witnesses or information.
Anyone who can help should call Suffolk Police on 101, quoting crime reference number 37/67028/23.
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