British authorities have issued a strong condemnation after rap punk duo Bob Vylan led the crowd in chants at the Glastonbury Festival calling for “free, free Palestine” and “death, death to the IDF” during a set broadcast live by the BBC.

The performance, which took place on the West Holts Stage just ahead of Belfast rap trio Kneecap, prompted the government to describe the comments as unacceptable. A BBC spokesperson stated that some of the remarks were “deeply offensive,” with a warning about “very strong and discriminatory language” displayed on screen. The broadcaster confirmed the set would not be available for replay on BBC iPlayer.

Police have announced they are reviewing video footage of both Bob Vylan’s and Kneecap’s performances to determine if any laws were broken.

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A statement from Glastonbury Festival said it “does not condone hate speech or incitement to violence of any kind from its performers.”

Following the incident, Culture Secretary Lisa Nandy contacted the BBC director general to request an urgent explanation regarding the broadcaster’s due diligence before airing the act. The government also expressed approval of the decision not to re-broadcast the performance.

Kneecap, who performed after Bob Vylan, have been in the spotlight recently after band member Liam Óg Ó hAnnaidh (Mo Chara) was charged with a terrorism offence for allegedly displaying the flag of banned group Hezbollah at a previous concert—a charge he denies.

Kneecap’s Saturday set, watched by thousands, included expletive-laden chants directed at UK Prime Minister Sir Keir Starmer, who had previously described their festival appearance as “not appropriate.” Ó hAnnaidh is currently on bail following a recent court hearing.

Avon and Somerset Police confirmed they are assessing video evidence from both acts to decide whether a criminal investigation is warranted.

“Glastonbury, I’m a free man,” Mo Chara said after appearing on stage.

“The prime minister of your country - not mine - said he didn’t want us to play, so f*** Keir Starmer,” Mo Chara told the crowd, wearing the keffiyeh scarf associated with Palestinians.

At least 30,000 people, hundreds of them with Palestinian flags, crammed into the West Holts stage in blazing sunshine to watch the trio, causing organisers to close the area.

After opening their set with Better Way to Live, which mixes English and Irish, another of the group’s members - M?gla? Bap, otherwise known as Naoise ? Caireall?in - said Mo Chara would be back in court for a “trumped up terrorism charge”.

Mo Chara told the crowd the situation over the lawsuit was stressful but it was minimal compared to what the Palestinians were going through every day.

Later in the set, Mo Chara accused Israel of committing war crimes, saying, “There’s no hiding it.”

Irwin Kelly, 40, said the trio got the crowd really involved in the set.

“Obviously it had a bit of controversy surrounding it,” he said.

“But it’s art, it’s performance.”

The Israeli embassy in the United Kingdom earlier said it was “deeply disturbed by the inflammatory and hateful rhetoric expressed on stage at the Glastonbury Festival”.

It did not immediately respond to a request for comment on Kneecap’s statements.

Access to the area around the West Holts Stage was closed about 45 minutes before Kneecap’s performance after groups of fans arrived to form a sea of Irish and Palestinian flags.

Starmer told the Sun newspaper this month it was “not appropriate” for Kneecap to appear at the famed music festival in the southwest of England.

Opposition leader Kemi Badenoch had said the public broadcaster BBC, which livestreams the festival, should not show Kneecap, and 30 music industry bosses asked organisers to pull the band from the line-up, according to a letter leaked by DJ Toddla T, cited by the Guardian newspaper.

In response, more than 100 musicians have signed a public letter in support of the group.

The BBC said on Saturday Kneecap’s set would not be live-streamed but said the performance is likely to be made available on-demand later.

Kneecap manager Dan Lambert told Reuters the group had expected calls for the performance to be cancelled.

During the hour-long set, Kneecap thanked organisers Michael and Emily Eavis for not bowing to the pressure.

Kneecap, whose third member has the stage name DJ Pr?va?, has said they do not support Hamas or Hezbollah.

Mo Chara said on Friday the group were “playing characters” on stage, and it was up to the audience to interpret their messages.

The performance followed months of debate over the band’s inclusion, after frontman Liam O’Hanna (stage name Mo Chara) was charged with a terrorism offence for allegedly displaying a Hezbollah flag and making supportive remarks about Hamas and Hezbollah at a London concert last year.

Both groups are banned in the UK, and expressing support for them is an offence. O’Hanna, who appeared in court earlier this month, has denied the charge and described his legal troubles as minimal compared to the suffering of Palestinians.

On stage, O’Hanna wore his trademark keffiyeh and gave a “shout out” to the Palestine Action Group, which has also recently been banned under anti-terror laws. Fellow band member DJ Provai wore a t-shirt dedicated to the campaign group.

Kneecap’s set was just one highlight of a festival that also saw surprise performances from Britpop legends Pulp and Scottish singer Lewis Capaldi, as well as headline acts including Neil Young and Olivia Rodrigo.

- with Reuters and PA