Police are currently negotiating with an armed man in a home in Pagham.
Sussex Police said: "Emergency services were called to a property in Harbour Road, Pagham at around 4.10pm on Sunday (28 August) following reports a 72-year-old man was using threatening behaviour and armed with a gun.
"A woman known to the man was also in the house, but she has now left and is safe and well. There are no reported injuries.
"The 72-year-old man remains in the house alone.
"A police cordon has been set up around the house and the road has been closed.
"Officers, including firearms officers, remain at the scene while negotiations continue."
There were reports on Facebook that armed police squads were at the scene, and that neighbours have been told by police to stay in their homes and lock their doors during the conflict.
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