An Egyptian naval vessel was set on fire during a clash with militants in the restive Sinai Peninsula on Thursday, the military said.
An Egyptian navy vessel caught fire off the coast of Sinai on Thursday after an exchange of gunshots with militants from the shore, the military said.
There were no fatalities among the vessel's crew in the exchange with "terrorists," according to a statement by the military spokesman, Mohammed Samir, on his Facebook page.
Samir did not say how much damage the vessel suffered and gave no details on the type of ship or the number of crew.
However, security officials said an unspecified number of crew members suffered injuries from the fire.
Firefighters have been trying to put out the blaze for more than three hours, the officials added.
The Islamic State group said it carried out the attack, SITE Intelligence Group reported.
The group's Egyptian affiliate, in a statement monitored by the US-based SITE, took responsibility for the attack, posting photographs on social media.
The vessel routinely patrols Egyptian territorial waters and has frequently been used to transport army and police personnel to mainland Egypt, the officials said.
The sea route avoids the overland journey through Sinai, where Islamic militants target government forces.
Authorities were also looking into the possibility that the vessel was first hit by a rocket from the shore or that suspected militants swam out to it and placed explosives, which were later detonated by remote control, said the officials, who spoke on condition of anonymity because they were not authorised to speak to the media.
On Wednesday, the military said it foiled an attempted attack on a military post on a highway linking Cairo with the Red Sea coast.
The driver of a car that was carrying 500 kilograms (1,100 pounds) of dynamite refused to stop at a checkpoint, drawing fire from the troops, the military said.
The car then swerved off the road and the driver was killed, the military said in a statement.
Egypt's Islamic State affiliate said it was behind Wednesday's incident, claiming the car's driver was a suicide bomber who had detonated his explosives' load, killing several soldiers.
The authenticity of the claim could not be independently verified, though it was carried by Twitter accounts affiliated with the group.
The military denied the claim.
Egypt faces threats from multiple insurgent factions, including the IS affiliate in Sinai, which the military says killed at least 17 soldiers in a July 1 assault there.
In another attack claimed by the IS group, Egypt's state prosecutor, Hisham Barakat, was assassinated in Cairo by a car bomb in late June.