Counter-terrorism police investigating the discovery of a "suspicious item" on a London train this week say they have found another such device in a search of a house in Devon, western England.
The house and neighbouring properties were evacuated on Saturday and a 200-metre cordon thrown around the area while specialist officers investigated.
The cordon has now been lifted and the device has been confirmed as not a viable explosive.
On Thursday morning, the first device was found on a train at London's North Greenwich station, near the Canary Wharf financial district and close to the O2 music venue.
Officers used a stun gun during the subsequent arrest in north London of a 19-year-old who was detained on suspicion of preparing terrorist acts. He remains in custody.
London's Metropolitan Police said on Saturday they had gone to a house in Newton Abbott, Devon, as part of their inquiries into the Greenwich incident.
"Whilst there, officers found an item they deemed suspicious," they added in a statement. "Officers evacuated the address and alerted Devon and Cornwall Police."
Police have not released whether the first device found was viable. It was made safe by a controlled explosion.
Britain is on its second-highest alert level of "severe", meaning an attack is considered highly likely.