Egyptian officials say they have foiled an attack on a container ship which was aimed at disrupting shipping in the busy Suez Canal.
Canal authority head Mohab Mamish said a "terrorist element" targeted a Panama-flagged vessel on Saturday, but it was undamaged.
There were reports of two blasts, but details of the attack are unclear.
Egypt's Sinai has been hit by a wave of violence since Islamist President Mohammed Morsi was ousted from power.
The unconfirmed reports said there were two explosions at 12:30 GMT on Saturday as the ship, Cosco Asia, passed through the waterway.
"The situation was dealt with strictly by the armed forces," Adm Mamish said in a statement.
The Suez Canal - between Port Said and Suez - is a vital global trade route between the Red Sea and Mediterranean.
It is unknown whether the attack was linked to the continuing protests by Muslim Brotherhood supporters against the 3 July ousting of President Mohammed Morsi by the army.
Hundreds of pro-Morsi protesters have been killed in a recent military crackdown and a further five civilians were reported killed in clashes on Friday between opponents and supporters of the deposed president.
The unrest has spilled over into the Sinai peninsula, where Islamist militants have carried out frequent attacks on the authorities. Two policemen were killed in separate attacks on Friday, the interior ministry said.
In a separate development, a top militant was arrested in Sinai on Saturday, Associated Press reported, on suspicion of involvement in an ambush last week in which 25 off-duty policemen were shot dead.
The group behind the attack is thought to be linked to al-Qaeda.
On Saturday, an al-Qaeda leader in Iraq released an audio message in which he called on members of the Egyptian army to defect.