The Islamic State militant group's affiliate in Egypt has put its name to Thursday's missile attack on a navy frigate off the country's Mediterranean coast in which it claimed to have killed all of the crew.
"In a blessed operation for which Allah facilitated its causes, the mujahideen were able to target a frigate of the naval forces of the apostate Egyptian army in the Mediterranean Sea...with a guided rocket," the Sinai Province group said in a message on Twitter.
"It led to its complete destruction and the elimination of all who were in it, and unto Allah is all praise and gratitude," the message continued.
The authenticity of the claim could be immediately verified, but the Twitter posts were accompanied by three pictures apparently showing a rocket flying toward the vessel, followed by a large explosion engulfing it.
The patrol boat was pursing militants off the coast of Rafah, a town in North Sinai, and had exchanged gunfire with them, state daily Al-Ahram's website reported, citing an Egyptian army statement.
Egyptian military spokesman Mohammed Samir was cited as saying the frigate caught fire during an exchange of fire with "terrorists" on the shore, and that no crew members were killed.
Samir did not specify the extent of the damage, but security officials said that a number of crew members suffered injuries during the attack, and several jumped overboard to escape.
The volatile North Sinai region, where Rafah is located, is a flashpoint for a mounting Islamist insurgency that has killed hundreds of members of Egypt's security forces since the army's 2013 ouster of Islamist president Mohamed Morsi.
Earlier in July, 21 soldiers were killed after simultaneous militant assaults on army checkpoints in the North Sinai towns of Sheikh Zuweid and Rafah, prompting fighting between troops and insurgents that left over 200 militants dead.
