The signs, posted on a median with overgrown weeds at the intersection of Burton Way and Doheny Drive, read: "Landscaping by L.A. City Council: 'We'd rather spend your taxes on welfare for illegals.'" L.A.'s seal was in the center of each poster, making it look like the signs belonged to the city.
They were taken down by Friday afternoon.
City Councilman Paul Koretz condemned the signs.
In a statement, Koretz said such messages have been turning up since, in his words: "Donald Trump empowered racists and bigots across the country."
Koretz adds: "The city of Los Angeles will never give in to these types of people."
The sign is the second of its kind to be spotted in Southern California. On April 5, a similar one was posted on Pacific Coast Highway in Malibu after the beach municipality proclaimed itself as a sanctuary city.
The sign read: "Official Sanctuary City: Cheap Nannies and Gardeners Make Malibu Great! (Boyle Heights, Not So Much)." Malibu called it an unfortunate prank.
A social media website claimed responsibility. It said its rogue work is part of a Republican art movement intended to show that the Los Angeles scene does not belong to the left wing.
It was unclear whether the same people are responsible for the prank in Beverly Hills.
The Associated Press contributed to this report.