Secret Service guards had to step in for Barack Obama and shoo off a photographer who was apparently pestering him for a picture Wednesday while he toured the Italian Market in Philadelphia.

The insistent picture-taker was trying to snap the photo to authenticate autographs collected to sell on eBay, according to a campaign spokeswoman, who said he was part of a group that earlier in the day tried to cut in front of a line of third-graders. Spokeswoman Jen Psaki did not indicate whether anyone in the group had acquired an autograph but said its members followed Obama to the market after being moved to the sidewalk for being "disruptive."

That's when things got testy. Here's the exchange:

Photographer: "Senator, can I have a quick picture with you?" (Obama declines and walks away.)

Photographer: "It will take you two seconds. Don't cram me, I'm not doing anything to anybody. Jesus."

(Later on ...)

Photographer: "Senator can I get a picture with you?"

Obama: "You are wearing me out, brother."

Photographer: "I got one with (Clinton) and I got one with McCain, come on Senator that's not right."

(Later on ...)

Photographer: "Senator, can I please, a quick one?"

Obama: "No, you know what, no."

Photographer: "Can I just say something to you real fast?"

Obama: "Yeah you can."

Photographer: "I had one with (Clinton) had one with Senator McCain."

Obama: "I am sure you do. Because when I was trying to talk to some kids -- and I know, look ..."

Photographer: "No, my wife is a school teacher and she was there, she had to go back and that wasn't right. Why won't you just take a picture with me? I'm not asking you for an autograph. It's for my family."

Obama: "Yeah well whatever. Just take it. I won't be smiling. Because you've been wearing me out ... No no, you've been really rude about it. But that's okay. Just take a shot. Take your shot because you were rude."

At that point, Secret Service stepped in and put a hand between him and Obama -- they did not end up taking a picture together.