LONDON (KGO) --Pictures showing metal spikes embedded in the sidewalk outside a luxury apartment building are causing a lot of controversy in London.
Opponents believe they're intended to keep homeless people from sleeping there, and thousands of people have signed an online petition titled "Remove the Anti-Homeless Spikes."
London Mayor Boris Johnson weighed in, tweeting a message urging the developer to remove the inch-high studs.
His tweet reads, "Spikes outside Southwark housing development to deter rough sleeping are ugly, self defeating & stupid."
Tesco, the parent company of Property Partners, denies the studs are aimed at the homeless. The company says they were put in place to stop people from smoking and drinking outside the building.
(ABC News contributed to this report)