A few hundred marchers took to the streets of downtown D.C. at lunchtime Tuesday and later gathered near the White House as part of the International AIDS Conference, which ended with the arrest of 13 protesters.

The marchers departed from Mount Vernon Square near the Walter E. Washington Convention Center at noon, complete with the aid of a D.C. police escort.

One marcher was Jean Ross, co-president of National Nurses United, a union and professional association of registered nurses that claims 175,000 members. She said her group was marching in support of a Robin Hood tax that would put a "small tax on Wall Street speculation" to pay for HIV/AIDS treatment.

The marchers were soon joined by a smaller group of protesters and stopped at the Bank of America branch next to Lafayette Square by the White House, pressed up against its door and windows, chanting, "Bank of America, shame on you!"

"I am sick of this disease. It's time to end it," said D.C. resident Michael Tikili, who says he has been living with HIV since 2009. "They keep telling us there's no money to end AIDS. There is money -- it's in Wall Street."

After a brief rally at Lafayette Square, protesters began tying red ribbons containing money, pill bottles, clean syringes and condoms -- all symbols of the battle against HIV and AIDS -- to the White House fence.

Protesters were warned three times by U.S. Park Police that their permit had been revoked and they needed to leave the sidewalk in front of the White House. Some of the protesters sat down in response; nine women and four men were arrested.

Shortly after the arrests, people began clearing out of the square, and police began cutting down the ribbons tied to the fence.

"You can cut the ribbons down, but people are still dying," one of the protesters called to police. "What are you going to do about that?"

More than 23,000 people are in town to attend the weeklong conference.