Armed police were called to Caerphilly town centre on Friday afternoon after reports that a gang was firing an imitation gun from a car.
Four teenagers from Senghenydd were arrested by officers on suspicion of possession of a firearm with intent to cause fear of violence.
Police had a call from concerned members of the public at around 1.15pm on Friday February 8.
A Gwent Police spokeswoman said: “We had reports from members of the public that they had seen some men in a car with an object that looked like a firearm.
“Four men were arrested. One aged 19, two aged 16 and one aged 17, all from the Senghenydd area arrested on suspicion of possession of a firearm with intent to cause fear and violence.
“All four have been released on police bail pending further inquiries and the imitation firearm has been seized.”
The arrests took place outside the Irish Tymes pub.