LONDON (REUTERS) - Counter-terrorism police investigating the discovery of a "suspicious item" on a London train this week said they found another such device on Saturday (Oct 22) when they searched a house in Devon, western England.
The house and neighbouring properties were evacuated and a 200m cordon thrown around the area while specialist officers investigated.
On Thursday morning, the first device was found on a train at 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 and remains in custody.
London's Metropolitan Police said on Saturday they had gone to a house in Newton Abbot, 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."
They later confirmed the Devon device was "not viable."
Police have not released details about the two items nor have they said whether the first, which was made safe by a controlled explosion, was a viable explosive device.
Britain is on its second-highest alert level of "severe", meaning an attack is considered highly likely.
Security has been stepped up on the London Underground network, police said Saturday (Oct 22), following the arrest of a 19-year-old man after a suspicious item was discovered on a Tube train.
"The public will see more officers, including armed police, in and around transport hubs," a Scotland Yard spokesman told AFP.
Armed police arrested the 19-year-old in London on Friday (Oct 21) under counter-terrorism laws in connection with the suspicious package found the day before.
An electric stun gun was used during the arrest on a busy shopping street, but no shots were fired.
The suspect, who was arrested on suspicion of the commission, preparation and instigation of terrorism acts, remains in custody on Saturday.
The item, found on a train at North Greenwich station, which serves the O2 entertainment complex in southeast London, was being forensically examined.
Britain's current national terror threat level has been set at severe - the fourth-highest of five - since August 2014, meaning an attack is considered highly likely.
The Times newspaper spoke of a "lone wolf" and said that the incident was "feared to be the first credible bombing attempt on the London transport network in more than 10 years".
Scotland Yard refused to comment on the report.
