DiCaprio splits with supermodel girlfriend

Film star Leonardo DiCaprio and his supermodel girlfriend, Bar Refaeli, have split up, as have former "Heroes" starlet Hayden Panettiere and her boxer beau, Wladimir Klitschko.

DiCaprio, 36, and Refaeli, 25, went their separate ways amicably, a source told People. The couple, who had been together since 2006 except for a six-month breakup beginning in 2009, had simply grown apart, the source said. Though the two had attended Anna Wintour's Met Ball in Manhattan on May 2, they barely appeared together there, reports said the next day, and went to separate social functions afterward.

Panettiere, 21, was seen with Ukrainian giant Klitschko, 35, as recently as the April 23 Tribeca Film Festival screening of the animated "Hoodwinked Too! Hood vs. Evil," for which the actress voiced the starring role. Klitschko -- the International Boxing Federation, International Boxing Organization and World Boxing Organization heavyweight boxing champion, who divides his time between homes in Florida and Germany -- told the German magazine Bunte of the 18-month relationship, "We have had a great time together. But more and more we realized how difficult it is to maintain a relationship when living on two continents."

Panettiere said to People magazine, "While we decided to split, we feel great sympathy and respect for each other and will surely stay close friends."