At least seven people died and 86 were wounded in a bomb attack at a crowded cafeteria at Jerusalem's Hebrew University on Wednesday.
The Palestinian militant group Hamas claimed responsibility for what is believed to be the first attack on an Israeli university in the current unrest. It was thought to have been the act of a bomber who escaped from the scene.
The Palestinian Authority issued a condemnation of the blast, and Jesse Jackson cancelled a meeting with Hamas leader Ahmed Yassin.
The Mount Scopus campus is close to the Arab neighbourhoods of the holy city. Israeli Jews, Arabs and foreign students mix freely in the university's Frank Sinatra International Student Centre, where the bomb exploded. The university is regarded as a rare enclave of tolerance in the near-two-year conflict.
According to al-Jazeera, the Arab satellite television broadcaster, Hamas said it had carried out the attack in revenge for the air strike on Gaza City last week in which one of their leaders was killed along with 14 other people.
White House spokesman Ari Fleischer said that the US president, George W. Bush, condemned the attack "in the strongest terms". "This terrorist attack underscores again the need for the Palestinian people and the Palestinian leadership to take action to halt terrorism so that peace has a chance in the Middle East," he said.
Alastair Goldrein, 19, from Liverpool who has been reading Jewish studies at the university for the past year, said: "There was a huge, huge explosion. Everything shook and then there was this deathly silence. I ran in and there were people lying around wailing, covered in blood. Scenes that are indescribable, clothes and flesh torn apart."
Mike O'Brien, parliamentary under-secretary at the Foreign Office, said:
"Nothing can ever justify the use of terror against innocent civilians to advance a political cause. Both the Palestinians and Israelis must take action to break the cycle of violence and to help the other party break the cycle of violence."