Police have warned parents to keep children and pets indoors after a "hungry" 7.5ft snake escaped.
The female boa constrictor, named Diva, was last seen in her tank at her owner's home in Broom Crescent, Ipswich, at about 6am yesterday.
The owner described the snake as "unfriendly" and said it might bite if approached. It is not, however, venomous.
A police spokesman said: "The snake is nocturnal and is likely to hunt at night and will bask in the warm grass or on rocks in the sun during the day.
"It will hide, for example, under sheds when not hunting or warming. She was last fed about three weeks ago and is due a feed.
"Suffolk Police cannot rule out a risk to the public and residents are advised to keep children and pets indoors.
"However, our understanding is that this snake will only feed on small animals such as mice and rats.
"It is possible the breeding season could have encouraged the boa constrictor to go out hunting."
Boa constrictors are commonly found in tropical forests in South America and are from the family of constricting snakes, which kill their prey through asphyxiation.