The interception was condemned by Lebanon and Syria, adding to regional tensions in the wake of last month's devastating Israeli offensive against the Islamic militants of Hamas who control Gaza.
Talks in Egypt to cement a long-term cease-fire in Gaza ran into obstacles yesterday. A Hamas delegation left Cairo without agreeing to a truce deal.
In an apparent slap at Hamas, Egyptian officials reported that security officers frisked the delegation returning to Gaza and confiscated $9.5 million to $11.5 million in dollars and euros. The cash was deposited in an account in Egypt, and the delegation was allowed to return to Gaza, a security official said. It was not clear what would happen to the money.
The Gaza fighting ended Jan. 18 when Israel and Hamas declared separate cease-fires. Some incidents of violence, notably rocket fire into Israel and Israeli airstrikes on arms-smuggling tunnels under the Gaza-Egypt border, have marred the informal truce, but Egyptian efforts to stabilize the situation appeared to be making progress.
It was unclear if the Hamas exit yesterday marked a crisis or a last-gasp push for more concessions in the group's indirect negotiations with Israel.
In violence late yesterday, the military said troops fatally shot a Palestinian who threw a grenade near the Gaza-Israel border. It said soldiers entered Gaza briefly to search the area.
Hamas and Israel refuse to deal directly with each other. Israel considers Hamas, which has sent dozens of suicide bombers into Israel, a terror organization. Many Hamas leaders stick to the group's ideology calling for destruction of the Jewish state, but some say they would accept a Palestinian state next to Israel.
The United States and other countries are considering using an international naval force to stem the flow of smuggled arms to Gaza, officials said yesterday after talks in Copenhagen.
After letting several ships from Cyprus sail into Gaza, the Israelis drew the line yesterday, banning the Lebanese vessel.
Israeli Foreign Ministry spokesman Yigal Palmor said Lebanon does not have relations with Israel, and there was no way of knowing who or what was aboard. "This kind of provocation is unacceptable," he said.
Reporters for the Arab television stations Al-Jadeed and Al-Jazeera, who were on the vessel, said Israeli sailors fired at the ship before boarding it and beating those on board. Gunfire could be heard in the background of the telephoned reports broadcast by their stations.
The navy said no gunshots were fired aboard the ship but Israeli sailors had to overcome some resistance on the vessel. The navy towed the ship to the Israeli port of Ashdod.
Israel pledged to deliver the aid supplies to Gaza over land. Palmor said the ship would be sent home.
Lebanon's prime minister, Fuad Saniora, condemned the seizure as a "blatant attack."