The Metropolitan Police's counter-terror officers will investigate online videos showing rap trio Kneecap calling for the death of British MPs and shouting "up Hamas, up Hezbollah".
A video emerged of the west Belfast trio at a November 2023 gig where one person from the band says: "The only good Tory is a dead Tory. Kill your local MP."
Both Hamas and Hezbollah are banned in the UK and it is a crime to express support for them.
Kneecap say they have never supported Hamas or Hezbollah and would not incite violence against any individual. They say the video in question has been taken out of context.
Some gigs featuring the band have been called off since the video emerged, most recently their Plymouth show, which was cancelled just two days after it was announced.
Organisers cited safety reasons, saying they had "taken advice from relevant authorities and agencies".
The group have since announced new Plymouth gigs at a different venue.
On Thursday, the Met Police said: "On April 22, we were made aware of an online video believed to be from a music event in London in November 2024.
"Following this, we were made aware of a further video, believed to be from another music event in London in November 2023.
"Both videos were referred to the Counter Terrorism Internet Referral Unit for assessment by specialist officers, who have determined there are grounds for further investigation into potential offences linked to both videos.
"The investigation is now being carried out by officers from the Met's Counter Terrorism Command and inquiries remain ongoing at this time."
In a statement earlier this week, Kneecap said they rejected "any suggestion that we would seek to incite violence against any MP or individual. Ever."
The statement says: "Let us be unequivocal: we do not, and have never, supported Hamas or Hezbollah"
They stated that "an extract of footage, deliberately taken out of all context, is now being exploited and weaponised, as if it were a call to action".
Referring to two MPs who have been murdered in the UK in recent years, the trio added: "To the Amess and Cox families, we send our heartfelt apologies, we never intended to cause you hurt."