A man thought to be armed with a knife brought the Jubilee Line to a halt on Friday after terrified commuters called the police.
Delays hit the line between London Bridge and Stratford around 9am after reports emerged that a man carrying a knife had been sighted on the train.
According to lbc.co.uk, police were first called to Canary Wharf station after passengers saw the man on the Jubilee Line, but he was also seen on the Central Line.
A British Transport Police spokesman told the Standard: "Officers were alerted to reports of a man carrying a knife on board a Central line train service on Friday, 6 March, shortly before 9am.
"The man is thought to have travelled on a Jubilee line service to Canary Wharf . Officers searched a train at Canary Wharf, but no one was found matching the description."
The IB Times reports that police are no longer looking for the man because no crime was committed.