Blac Chyna's 18-year-old boyfriend allegedly attacked two teen girls at Six Flags just minutes before Chyna was seen throwing her daughter's stroller around like a weapon.
We got Alexis, who's also 18, speaking out for the first time about Sunday's melee, which she says started when she spotted Chyna's daughter, Dream, in a stroller. Alexis says Dream was being pushed by a nanny and Alexis complimented the nanny on how cute Dream was.
Alexis claims she patted Dream's hand, which Chyna noticed and warned her not to touch the kid ... and 15 minutes later threatened to whoop her ass.
Alexis claims a physical altercation started with Chyna's bf, YBN Almighty Jay, punching her and her sister several times. Alexis claims she never traded blows with Chyna, and Six Flags security quickly intervened, advising everyone to go on their way without filing a report.
A source close to Chyna tells us the reality star snapped because Alexis called her a "hood rat." Alexis denies that.