Pol Lt-Col Apichart Thongchandee, a Khlong Ton police station inspector, said the clash between two rival groups of teenagers took place on Ekamai Soi 30 about 8am.
Many cars and vehicles parked on the road were damaged but no one was injured during the fight, he said.
The teenage groups were from Rong Poon community in Bangkok's Makkasan district and had been confronting each other for a long time, he said.
"We now know who all the attackers are. After questioning all the witnesses and inspecting the firearms, we will seek arrest warrants for them," said the police inspector.
During questioning, one of the teenagers, whose name was withheld, told investigators that the two groups of teens were partying at an entertainment venue in Phet Phraram area.
While they were partying and drinking, they competed against each other in "Gangnam Style" dance. The two sides began to quarrel as the competition got more intense and one of the groups later left the venue, he said.
"Four people from the group returned at 6am and fired several shots into the sky. I tried to mediate and they agreed to leave," the teenager said.
"Three of them later returned about 8am and they sprayed bullets in all directions like in action movies. I and other people there were running for our lives."
Another teenager told police that his friends and the attackers were provoking each other by doing Gangnam Style dance moves.
"I thought the issue was settled but the other group refused to end it and they decided to fire at us while we were unprepared," he said.