Three newly hatched peregrine falcon chicks have been stolen from their nest on top of a building in Kingston.
Wildlife officers said that thieves may have risked "life and limb" to get to the chicks, which can fetch £10,000 on the black market. The RSPB said that the birds are often captured for use in falconry, but that thefts from urban areas were unheard of.
"Peregrines are more vulnerable in remote areas," Duncan McNiven, of the RSPB's investigations team, said. "For thieves to strike in the middle of town is a bold move and a worrying development." Peregrine falcons, a protected species, have increasingly moved to urban areas in recent years.