Source: BTPLondon/Twitter

POLICE IN LONDON are searching for two men after gas was released on a Tube carriage in the city.

British Transport Police said a number of people required treatment at Oxford Circus after a suspected release of CS gas, the primary component of tear gas, at around 9.15am.

CCTV images show two men whom police are seeking to trace following the incident.

Their initial inquiries suggest that the gas was used during a fight between a group on board the train.

Police also said that paramedics treated a number of people for coughing, but added that there are no further concerns for their health.