Updated at 2:40 p.m. ET
A terrorist attack that targeted a mosque in Egypt's Sinai Peninsula has left at least 235 people dead and as many as 100 wounded Friday.
The death toll makes it the biggest attack since the conflict in the North Sinai started six years ago.
The Middle East News Agency said the bombing and shooting attack took place in the city of Arish, which is about 30 miles from the border with the Gaza Strip.
Police officers told The Associated Press that men in four off-road vehicles shot at worshippers who were at the al-Rawdah mosque for Friday prayers.
Egyptian President Abdel-Fattah el-Sissi spoke to the country on state television, condemning the attack and encouraging the country not to lose hope.
"The armed forces and the police force, will avenge our martyrs, and restore security and stability, with utmost force during the coming short period, this is our [response]," Sissi said. "We will respond [to] this act with brute force in facing those extremist terrorist [factions]."
He ordered the government to allocate compensation to the families of the dead. He also announced three days of national mourning.
Officials from around the world, including Israel, Iraq, France and the United Kingdom, condemned the attack. President Trump denounced the attack hours later.
Officials from the U.S. Embassy in Egypt offered the following message of support:
"Today's terrorist attack on worshippers attending Friday prayers at a mosque in Arish was an unconscionable act of cowardice and hate. The Embassy extends heartfelt condolences to the families of those who were killed and we wish a speedy recovery to those injured. As Egypt battles the scourge of terrorism, the United States stands committed to the safety and security of Egypt and its people."
It is not known yet who planned and carried out the assault on the mosque, but there has been an Islamist insurgency in the region for several years. Officials said a midair explosion of a Russian jet in 2015 over the Sinai was the work of terrorists. Sissi said the plane bombing was meant "to hit relations with Russia," which has conducted military interventions in Syria's civil war ostensibly to target the Islamic State there.