By midday, the Batkid's adventure had become a sensation on Twitter, with even the White House chiming in with its support.
At the cable car rescue, hundreds of people jostled for space, as the boy dressed in a Batman costume and accompanied by an adult Batman impersonator emerged from the Lamborghini to rescue a woman. Miles is a leukemia patient who's now in remission.
Streets of San Francisco are PACKED for BatKid. Greates thing EVER. pic.twitter.com/HAZkaK1o3y— John Nolte (@NolteNC) November 15, 2013
He looked overwhelmed and was bashful, though he was seen later in the day giving high-fives to onlookers. The damsel sat on the street in a dress and thigh-high black boots. She had a handkerchief around her mouth and her hands were bound behind her back. Batman and Batkid sprang into action, with the aid of a trampoline, as the crowd roared.
They rescued the woman and disabled a plastic replica bomb she was tied to.
The two masked superheroes then took off to nab the Riddler as he robbed a downtown bank.
A flash mob will summon Batkid later in the day for another crime -- the diabolical kidnapping of the San Francisco Giants mascot -- Lou Seal -- by the Penguin. A grateful Mayor Ed Lee will give Miles a key to the city after the crooks are corralled.
"When you have an illness, it's very important to know you have a support system," said Gina Futrell, 51, who was going to take part in the flash mob. Futrell has multiple sclerosis. "I have an extremely strong support system, and I hope he does too. He's such a little hero."
Miles, who lives in Tulelake in far Northern California, didn't know what was in store for him and thought he was in San Francisco just to get a Batman costume so he could dress like his favorite superhero, KGO-TV reported.
He was diagnosed with leukemia when he was 18 months old and ended treatments in June.
His father, Nick Scott, thanked the Greater Bay Area Make-A-Wish Foundation and the estimated 7,000 people who will help make his son's wish come true.
"All the doctors, nurses and all the other parents that have to deal with the same thing we're going through. I hope they get a conclusion to their illnesses like we're getting," Nick Scott told KGO-TV.
Make-A-Wish has fulfilled similar wishes across the country. In Anaheim, a child became Batman's sidekick, Robin; and in Seattle a child was a secret agent, said Jen Wilson, a spokeswoman for the local organization.
Watch a live feed of the action here.
The San Francisco Chronicle, KGO-TV and thousands of volunteers were participating in the event. Miles was supposed to see a broadcast in the morning with Police Chief Greg Suhr calling for his help.
The Chronicle planned to distribute special-edition newspapers with the headline, "Batkid Saves City," in Union Square, where the flash mob was set to gather.
"This has turned into a full blown phenomenon," Suhr said Thursday.
Associated Press writers Channing Joseph and Sudhin Thanawala contributed to this report.
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