Around 2,000 protesters blocked car ferries from crossing the Suez Canal after a court ruled that 21 soccer fans would be sentenced to death, witnesses told Reuters.
Protesters reportedly also untied moored speedboats used to supply shipping in a bid to disrupt passing vessels.
Military police recovered five boats and brought them back to shore in Port Said, but two were still drifting, one witness said.
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The band announced at a free concert on Friday that they would take over the event's Pyramid stage on Saturday June 25.
The victims were collecting permits and escorts a day after their home town was liberated from the extremists.
Scotland Yard said the male youths will appear in custody at Westminster Magistrates' Court on Saturday.