The Met said in a statement: "Police were called.to reports of an explosion and people running at Southgate underground station".
First reports to police said a suspicious noise came from inside Southgate tube station.
It is understood some people have been injury but not seriously.
People are being asked to avoid the area.
Trains are now not stopping at Southgate Tube station due to concerns over the suspicious package.
"I was at Southgate Station when this commotion started".More news: Former Oregon player Leiato found dead after crash
British Transport police said its officers also responded to the call, though the force could not immediately offer further details. Cordons are in place and the station is closed.
Police are now investigating the incident.
The busy underground station, which is located in north London, was evacuated at around 7 p.m. local time following the explosion, cops said.
"The scene has been examined by specialist officers".
'Enquires are ongoing to establish the cause of the reported explosion, which appears to have been minor.