"Well the city should try to prevent this," says tourist Kiet Le.
Le was visiting the city with a friend from Atlanta. He said this kind of graffiti leaves tourists with a bad impression of San Francisco.
"Tourists from other countries, they may not think that this is a safe place to visit. So they should clean it," says Le.
"These guys take fame in how long their vandalism gets to stay up," says Mohammed Nuru of the San Francisco Department of Public Works.
Nuru oversees the department's graffiti abatement crews. The day after the I-Team called, he sent workers to paint over the graffiti, but the vandals struck back just as quickly.
"Two days ago this wall was clean, and look at it now," says Nuru.
He found the spray can they left behind.
"So not only are they defacing property, they're littering the city with cans. Some of these cans actually contain toxics, and this is why this type of behavior must stop," says Nuru.
Nuru says the public should call the city's 311 phone line to report graffiti in their neighborhood.
Department of Public Works crews take photographs to document every instance of graffiti in the city. The photos are then used to prosecute vandals after police arrest them.
"The day we catch this guy we are going to go and recoup costs for all these tags that were found anywhere in our city," says Nuru.
This job cost about $1,000, and Nuru says stairwells are just one more front in the city's constantly moving battle against graffiti.
"This is on our radar screen now and we're going to check this every day, and we're going to clean it until these guys leave this property alone," says Nuru.
The city is offering a $250 reward to people who provide information that leads to the arrest and prosecution of a graffiti vandal. Authorities say you should call 911 to report vandalism in progress.
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