Armed police, dog units and paramedics have been attending an incident in Rowlands Road In Worthing this afternoon.
Police executed a warrant just after 2pm, which has resulted in a cordon going up and armed police attending the scene.
A Sussex Police spokesman said:
"Police have attended an address in Rowlands Road, Worthing, to execute a warrant shortly before 12pm on Thursday (May 9).
"Officers remain at the scene and the road remains closed while the incident is dealt with.
"Police have thanked the public for their patience."
Traffic in the area remains slow.