Armed officers and emergency services have been in Worthing dealing with an on-going police incident.
Sussex Police say they were called to a property in Broadwater Street West at 8:35am this morning following concerns for the welfare of a man.
Officers have tweeted to say it was not a firearms incident.
Meanwhile police have advised Broadwater C of E Primary School, Lancing Prep and Worthing High School that there is no need to keep pupils and staff inside while the ongoing incident is being dealt with.
The A24 going through this location is currently closed while officers are dealing with the matter.
A man has been arrested in connection with the six hour standoff with police.
Officers attended the scene following concerns for a man who was threatening to harm himself.
The man refused to come out of the flat for police until just before 2.30pm when he was subsequently arrested on suspicion of making threats to kill and threats to cause criminal damage. He remains in custody while the investigation is ongoing.