Fox spokeswoman Gaude Paez said Tuesday the episode has been removed from Fox.com and Hulu.com.
In the episode, protagonist Peter Griffin is asked by sports announcer Bob Costas about his performance at the marathon. A flashback shows Peter mowing down runners with his car.
"I'll tell ya, Bob, I just got in my car and drove it," Griffin says. "And when there was a guy in my way, I killed him."
Later, Peter befriends a terrorist who, unbeknownst to him, is plotting to blow up a bridge. When Peter dials a cellphone the friend has given him, explosions and screams are heard. On some websites, an edited clip has been circulating that fuses the two scenes, making it seem — incorrectly — as if the explosion was at the marathon. Some commenters have implied that the show "predicted" the bombings.
"Family Guy" creator Seth MacFarlane took to Twitter on Tuesday to vent anger over the edited clip and offer condolences to victims of Monday's bombings at the marathon.
"The edited 'Family Guy' clip currently circulating is abhorrent," MacFarlane tweeted. "The event was a crime and a tragedy, and my thoughts are with the victims."