The killing has shocked neighbours in the residential street, which is located on the outskirts of Colchester.
A number of homes were sealed off on Sunday as police searched for clues.
Empty bottles of vodka and cans of lager could be seen strewn across the front gardens of properties in the street.
Marie Partner said a woman and her teenage daughter, who were hosting the party, had spoken to neighbours on Saturday to apologise in advance for any extra noise.
Ms Partner, who has lived in the street for nine years, said:
The mother and daughter took it upon themselves to tell the neighbours there was a party taking place and to apologise in advance if there was slightly more noise than normal. Usually it's very quiet around here.
It's so sad. The first I knew about it was seeing the police arrive and the area being cordoned off.
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