Washington, March 4 : Actress Katherine Heigl is reportedly facing heat on the set of her latest flick `Five Killers' for throwing diva tantrums.

The `27 Dresses' star was allegedly being "extremely unprofessional", chipping appointments and making outlandish demands.

Heigl was said to have been insisting that she be jetted in a private plane to reach the movie's international destinations, along with demanding "crazy amounts of security."

"Heigl reportedly refused to film any scenes until her pregnant assistant ran around and got her a Coke Zero," Fox News quoted a source as saying.

"She refused to eat lunch next to anyone or have anyone speak to her once the cameras stopped rolling. No one on the crew likes her," the source added.

Another source said: "She has a sense of entitlement that is really off-putting. Many directors that she's worked with in the past do not want to work with her again." (ANI)