Kings Cross station was evacuated by armed police as a man was detained on suspicion of drug offences.

Armed British Transport Police (BTP) descended on mainline platforms shortly after 3pm to meet a train coming into the London station, the force said in a statement.

Officers arrested a 40-year-old man on suspicion of possession with intent to supply a Class B drug over an hour later, at 4.15pm.

As rush hour was set to start in the capital, closed platforms were evacuated as officers made inquiries. Platforms have since re-opened, BTP tweeted, thanking passengers for their co-operation.

Trains travelling to and from from the station were delayed by up to 30 minutes, according to the National Rail website.

By 5pm, trains were running normally once again, according to the rail organisation.

Passengers at the station tweeted updates as the scene unfolded.