Los Angeles: `Twilight` star Kristen Stewart came face-to-face with her ex-boyfriend Robert Pattinson`s rumoured new girlfriend, Riley Keough.
The pair bumped into each other at rocker Joan Jett`s recent concert at West Hollywood`s House of Blues, reported Showbizspy.
Stewart and Keough first met in 2010 while co-starring in `The Runaways`, a biopic about Joan`s life.
Stewart, 23, starred as Joan in the film, while Keough, 24, played fellow female rocker Marie Currie.
"It was weird when they saw each other, because Kristen didn`t look very happy when she walked over to give her a hug," a source said.
"They spoke for like two minutes and then Riley and her girlfriend walked away. Kristen watched the show from upstairs and I am pretty sure Riley kept her distance and was watching from downstairs," it added.
Recent reports revealed that Pattinson and Keough have been `hanging out and hooking up`.
"She is the first girl he has liked since Kristen. They`re having a lot of fun," the source said.