British Transport Police said officers were called to Worthing railway station at around 7pm last night (Wednesday, September 11).
"This followed reports of teenagers believed to be in possession of a firearm at the station,” a BTP spokesperson said.
"Officers attended, including firearms officers, and conducted a thorough search of the area and no trace was found.
"Enquiries into this incident are ongoing, and anyone with information is asked to contact BTP by texting 61016, quoting reference 539 of 11 September.”
At least 15 police officers, some armed with guns, were seen on the north side of Broadwater Bridge around 8.45pm.
Photos showed the police dog unit was among the multiple police vehicles in attendance at the incident.
Scroll down to see the photos from the scene.
1. Worthing armed police incident
At least 15 police officers, some armed with guns, were seen on the north side of Broadwater Bridge around 8.45pm. Photo: Eddie Mitchell
2. Worthing armed police incident
At least 15 police officers, some armed with guns, were seen on the north side of Broadwater Bridge around 8.45pm. Photo: Eddie Mitchell
3. Worthing armed police incident
At least 15 police officers, some armed with guns, were seen on the north side of Broadwater Bridge around 8.45pm. Photo: Eddie Mitchell
4. Worthing armed police incident
At least 15 police officers, some armed with guns, were seen on the north side of Broadwater Bridge around 8.45pm. Photo: Eddie Mitchell