Jay Leno's really taking it on the chin over his joke about Mitt Romney last week.

Leno has taken heat from a religious group after cracking that presidential contender Romney keeps the Golden Temple in Amritsar, India, as his summer home. And how he's being sued by a religious organizer who claims that Leno libeled the entire Sikh religion with his joke.

In court papers filed in Los Angeles Superior Court on Tuesday and obtained by TheWrap, Dr. Randeep Dhillon, who does business as Bol Punjabi All Regions Community Organization, claims that Leno "hurt the sentiments of all Sikh people in addition to those of the plaintiff" with his joke. Dhillon further claims that Leno's joke "clearly exposes plaintiff, other sikhs and their religion to hatred, contempt, ridicule and obloquy because it falsely portrays the holiest place in the Sikh religion as a vacation resort owned by a non-Sikh."

Claiming libel, Dhillon is seeking unspecified damages, plus court costs.

Since making the joke -- which was a riff on Romney's wealth -- Leno has taken heat, with one group launching an online petition [4] against Leno. The petition claims that Leno has a history of making discriminatory comments about the Sikh religion.

"Previously, in 2007 he called Sikhs 'diaper heads.' In 2010, he remarked, falsely so, in his monolog that President Obama could not visit Sri Darbar Sahib because of requirements of wearing a turban," the petition reads. "Clearly, Jay Leno's racist comments need to be stopped right here."

(The petition may be referring to a 2007 joke that Leno made about astronauts on a shuttle mission being so drunk that they wore diapers on their heads -- a reference to shuttle astronaut Lisa Nowak, who according to police wore adult diapers on a lengthy car trip to confront the girlfriend of her fellow astronaut, whom she was attracted to. Obama's canceled 2010 visit to Amritsar, which some attributed to his refusal to wear a scarf, was a widely reported story that Leno had commented on.)

NBC had no comment on the lawsuit.

Pamela Chelin contributed to this report.