It started when Alonso picked up her mother from a Miami flight and spotted Penn in an American Airlines lost luggage area Sunday.
Alonso, born in Cuba and raised in Venezuela, says her “heart stopped” when she saw the actor, to whom she’d written an open letter last year to say she was “appalled” by his public support of Hugo Chavez.
She told Page Six: “I was very calm. I said, ‘I would like to talk to you.’ He said, ‘I have nothing to say to you . . . You have been saying a lot of things about me in the press.’ I said, ‘How can you defend Chavez?’ ”
The argument escalated from there. Alonso relates: “I said, ‘You are a communist, Sean Penn.’ He said, ‘You are a pig!’ So I said, ‘And you are a communist [bleep]hole! Is it great to live the way you do as a communist?’
“I went back to my mother, and he started yelling at us,” Alonso told us. “I yelled back, ‘Communist [bleep]hole!’ Nearly 60 people were watching, shocked. My mother wanted to clap, but she couldn’t because she was in a wheelchair and she had a small dog in her lap...”