Hundreds of homes in Ipswich are currently without water.
Homes in east Ipswich and parts of Bramford are experiencing low pressure, or have no water at all.
The issue was first reported to Anglian Water at around 7pm on Saturday.
A statement on the Anglian Water website said: "We're really sorry but some customers in Ipswich may have very low water pressure or no water at all.
"We're working hard to identify the cause so that we can get your supply back to normal as soon as possible."
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