An escaped tiger has killed a visitor at San Francisco Zoo and mauled two other men.
It happened a year after the same animal attacked a park employee.
The Siberian tiger attacked the man just as the zoo was due to close. It was shot and killed by police while it was on top of another victim.
Reports said the dead man, aged 23, was attacked near an outdoor tiger enclosure. The two injured men were in a cafe a couple of hundred metres away.
They are in stable but critical condition at San Francisco General Hospital.
Officials could not say how the nine-year-old tiger, named Tatiana, escaped and the incident is under police investigation.
The zoo's tigers are kept in an open grotto, not a cage, separated from the public area by a moat 5.5m wide and 6.1m deep and a wall taller than 6m.
The 100-acre park was evacuated after the attack, but attendance was low at the time because of the Christmas holiday.
