A mystery caller knocked on a woman's door - and left a four-foot snake on her doorstep.
The South American male boa, dubbed Kojak by officers, was abandoned at the house in Cricklewood, north London, in the early hours today.
The resident told police a young woman knocked on her door and asked for Andrew before walking off and leaving a pillow case behind.
When the confused householder saw the case was moving, she looked inside, found the snake coiled up at the bottom and called police.
A Metropolitan Police spokeswoman said the snake is "friendly", in good condition, and appears to have been handled before.
It was housed in an office at Colindale police station for several hours before being taken to London Zoo.
The spokeswoman added: "If you are the owner of the boa and wish to be re-united with your pet, or have information about where he has come from please call police on 0300 123 1212.