NAPERVILLE, Ill. -- A cashier no longer works at a Naperville gas station after a video showed him questioning Hispanic customers' citizenship.The video went viral and drew protests to Bucky's Convenience Store. After a bike ride Tuesday, the Fernanda sisters, who are visiting from Mexico, and other relatives stopped at the gas station.One of their cousins from Naperville, Indira Buitron, 15, went inside to buy a bag of chips. Indira said the male clerk looked at her family waiting outside and asked her if her Mexican cousins were legal."I was really confused on why he wanted to know if they are illegal or not, so when I got out of the gas station I told my mom," Indira said.Another Naperville cousin, Carolina Buitron, then went inside to confront the clerk."I asked him, oh so you want to be a racist. I was like that's not OK. He said you need to leave; I said I don't need to leave. He said I'm American; I said I'm American too, I was born here," Carolina said.The confrontation escalated, the clerk told the family they need to go back to their country and made threats about calling ICE.On Wednesday, Bucky's released a statement sayingThursday morning, Bucky's said that the cashier no longer works for them."I was mortified that this employee felt it was OK for him to speak to anyone in that manner," said Liz Albert, a Wheaton resident.The clerk's comments come on the heels of President's Trump's racist tweets telling some congressional women of color to go back to the countries they come from.Trump supporter Bob Ahlgren thought the gas station protest was about that incident until he learned what the clerk said to the family."I don't disagree with them now that I know what is going on. If that was my place and employee and he disrespected people like that I'd lay him off too," Ahlgren said.The Naperville Police Department is investigating the incident. They released a statement regarding the incident: