Two people have been hospitalised and are in a "critical condition" following a "senseless" knife attack at Kennington Underground Station in London last night, authorities have said.

One person was stabbed and another received slash wounds before the attacker - who is believed not to be known to the victims - fled the scene.

Emergency services were called to Kennington Station at around 10.35pm last night after receiving reports a man had been stabbed on one of the platforms.

Another victim was injured after heroically trying to intervene to prevent the attack, police said.

Emergency services were called to Kennington Station at around 10.35pm last night

A major manhunt for the suspect has been launched by authorities - but no arrests have yet been made.

A British Transport Police (BTP) spokesperson said: "The injured victims were taken to hospital, where they remain in a critical but stable condition."

BTP Detective Inspector Paul Attwell said: "We understand that people will be worried by this senseless attack.

"Our teams have been working throughout the night, aided by CCTV footage, forensics and detailed accounts from witnesses at the scene.

Images posted to social media showed the first attack in Beckenham yesterday

"We believe that one of the victims was injured after bravely stepping in to try to prevent the attack."

Police have urged members of the public with any helpful information to contact British Transport Police by texting 61016 or calling 0800 40 50 40, quoting reference 728 of March 27.

This is the second shocking knife attack on London's transport networks in the last 24 hours alone; yesterday, footage emerged of a man attacking a fellow passenger with a large knife on a Southeastern Railway train between Shortlands in Southeast London and Victoria Station.

As in Kennington, a police investigation is underway - but no arrests have yet been made. The two incidents are understood to be unrelated.

Referring to the attack on the Southeastern train yesterday, a BTP statement read: "Detectives are appealing for witnesses to come forward after a man was seriously injured at Beckenham Junction today.

"At around 3.56pm today (March 27), we received reports of two men fighting while entering a train at Shortlands (railway station). A man sustained serious injures consistent with being stabbed.

"Officers attended, alongside colleagues from the Metropolitan Police Service and the London Ambulance Service, and the victim was taken to hospital with life-threatening injuries."

Again, BTP urged members of the public to reach out if they had any helpful information - this time, quoting reference 397 of March 27.