Mark Wahlberg says he "had no idea" a punch line from the movie "Ted" would offend people with Lou Gehrig's disease.
"I didn't know anything about it," the actor told "The Tommy Show" on 94.7 Fresh FM radio in Washington, D.C., Thursday.
The line, "From one man to another, I hope you get Lou Gehrig's disease," shocked movie-going ALS patients and advocates, who say it crossed a line.
"I didn't expect to go to a movie and sit with an audience laughing at the expense of people with ALS," said Randy Pipkin, who was diagnosed with Lou Gehrig's disease in 2005. "I think the message this film sends out is a huge slap in the face to people dying from this horrific disease."
Lou Gehrig's disease progressively robs people of their ability to move, speak, eat and breathe. There is currently no cure.
"Obviously, you know, it wasn't our intention to really offend anybody," said Wahlberg, who later agreed the film, written by "Family Guy" creator Seth MacFarlane, offended people "across the board." "Seth wrote the material, so you've got to take it up with him."
MacFarlane did not immediately respond to ABC News' request for comment.
"Ted" scored $54 million at the box office last weekend, and the offensive punch line has been making the rounds on Twitter ever since.
"We just want to stop this alarming trend before it becomes too widespread," Traci Bisson of the ALS Therapy Alliance, a Boston-based advocacy group, said in a statement. "We want to make it clear that ALS, or Lou Gehrig's disease, is not a laughing matter for people and families suffering from this life-threatening illness."
MacFarlane is famous for his boundary-pushing humor. But Jeff Lester, a self-professed MacFarlane fan with ALS, says the joke went too far.
"This line from Ted is something that never should have been said much less survived the editing process for a major movie release especially as a punch line for a comedy," Lester wrote in an open letter to MacFarlane and Wahlberg posted on Facebook. "When you wrote or said, 'I hope you get Lou Gehrig's Disease,' were you thinking how funny it would be for my children to hear when they have friends or classmates repeat this line?"
Lester said he condemns MacFarlane for writing the line and Wahlberg for speaking it, but added, "From one man to another, I hope you or anyone you know or love NEVER GETS Lou Gehrig's disease."