Anti-Israel activists disrupted a performance this week by the Jerusalem Quartet at England's largest arts festival.
The Israeli classical ensemble was playing at the Brighton Festival on Tuesday evening when the protest took place.
Eight demonstrators from the Brighton and Hove Palestine Solidarity Campaign shouted "Israel is guilty of war crimes against the Palestinians" and chanted "Free Palestine". They were thrown out by security guards.
Before the performance Festival director Andrew Comben had made an announcement warning the audience of the likelihood of disruption, following an earlier protest outside the Brighton Dome venue.
The Quartet was performing Schumann's Piano Quintet, alongside Russian pianist Alexander Melnikov, when the protest took place.
The musicians played on through the disruption and were given a standing ovation. The Quartet later tweeted: "Repeated disturbances in our concert in Brighton. Pity these misguided souls don't do something that might actually make a difference."
In a statement the musicians said: "The Jerusalem Quartet comprises four Israeli citizens, with no direct connection with, or patronage by, the government of Israel.
"We no more represent the government of our home country than the audiences for whom we perform, or indeed protesters, represent the government of their country.
"We encourage honest and respectful discussion concerning any topic at appropriate times and places. We do not believe the concert hall represents an appropriate forum for such discussion.
"We are musicians. We wish for our audiences of all persuasions, nationalities, and ethnicities to enjoy our music."
The protesters said they had acted on behalf of the Palestinian Campaign for the Academic and Cultural Boycott of Israel (PACBI).
"These musicians are cultural ambassadors for an apartheid state and as such should not be performing at the Brighton Festival," they said in a statement. "The festival guest director's mission statement affirms that the role of the festival is to 'remind us of the positive changes we can all make to improve our world for future generations'. Using music to whitewash the apartheid state of Israel should have no place here."
But concert-goer Ian Thompson wrote on the festival's website: "I was so ashamed and angered by the interruptions to the programme. Nevertheless, hair-on-end moments were delivered throughout a very affecting concert by five virtuosi. Wonderful music from a world-class group."
UK performances by the Quartet have repeatedly been disrupted, including at Wigmore Hall in April 2010 and in Edinburgh in 2008.