Liam Hemsworth cheated on Miley Cyrus with January Jones?

Liam Hemsworth allegedly cheated on Miley Cyrus with 35-year-old January Jones, according to Star magazine.

Miley Cyrus and Liam Hemsworth have been engaged for eight months.

The 23-year-old Australian actor was pictured arriving to the Chateau Marmont in Hollywood without Miley Cyrus.

January Jones was also at the event, and apparently the actors were seen getting cosy when they thought others weren’t looking.

“It looked like they had some hot chemistry. They were all over each other – and they even kissed!” a source said.

Liam Hemsworth and January Jones were also pictured in the back of the same car after partying Saturday evening.

Miley Cyrus meanwhile turned up solo to Elson John’s AIDS Foundation gala on Sunday night.

The 20-year-old singer and actress recently gushed about her relationship with Liam in the new issue of Cosmopolitan magazine. Asked what she values most in her life, she said she is most proud of her connection with her fiancé.

January Jones has previously been linked to Ashton Kutcher, Josh Groban and Jason Sudekis, and has a 17-month-old son, Xander, from a previous relationship.

The identity of Xander’s father remains unknown to the public after January Jones chose to leave his name off of the birth certificate.