Police were called around 7.40pm on Friday (October 22) to reports of a man in possession of a weapon.
As officers attended the scene in Horsham Road, two people suffered injuries consistent with being caused by a bladed article.
The victims were taken to the Royal Sussex County Hospital and East Surrey Hospital, where they remain in serious but stable conditions.
A 32-year-old man was safely detained with the use of a Taser and a weapon was seized. He was arrested on suspicion of attempted murder and taken into custody.
Detective Inspector Jason Hazzard said: “This was a serious and distressing assault on two people, and residents can expect to see a continued police presence in the area while our investigation is ongoing.
“We would like to hear from anyone who saw what happened, or who may have captured any relevant mobile phone or dash cam footage of the incident.
“We ask people not to share this footage on social media but to get in touch with us so it can be used to support our ongoing investigation.”
Anyone with information is asked to report online or by calling 101 quoting Operation Slope.
Alternatively, you can contact the independent charity Crimestoppers anonymously on 0800 555 111.