Actress/director JENNIFER WESTFELDT and her boyfriend JON HAMM fell victim to robbers during a recent trip to London.

The couple was in the U.K. to promote comedy/drama Friends With Kids earlier this month (Jun12) when a thief swiped Westfeldt's hotel key card from her handbag and ransacked the pair's room.

A source tells America's Life & Style magazine, "They were dining at a restaurant and Jennifer's purse was snagged by someone. That person took the hotel key in Jennifer's purse, which had the hotel name on it, and robbed their room. They had to contact the police; it was horrible."

The stars reported the crime to local authorities, who are currently looking into the matter, and Westfeldt admits the scary incident ruined the whole trip.

She says, "What a mess... It is under investigation."

Westfeldt directed Friends With Kids and co-stars in the movie alongside Mad Men hunk Hamm, Kristen Wiig, Megan Fox and Adam Scott.

06/26/2012 8:58