It was the deadliest battle in the region since the 1973 Arab-Israeli war.
The Egyptian army said that more than 100 militants and 17 soldiers were killed, Reuters reported. The Associated Press cited Egyptian officials as saying that 64 soldiers, 90 militants and four civilians died in the attacks carried out by an Islamic State affiliate called the Province of Sinai.
The group later claimed responsibility for the attacks, saying it staged three suicide bombings as fighters targeted 15 army and police positions, the Associated Press reported.
Israel's Defense Ministry shut the nation's border crossing into Gaza and another into Egypt in response to the attacks.
The White House strongly condemned the violence and offered support to the Egyptian government.
"We extend our deepest condolences to the families of the deceased and the government and people of Egypt, and wish for a speedy recovery for those who were injured," spokesperson Ned Price said in the statement.
"The United States stands resolutely with Egypt amidst the spate of terrorist attacks that have afflicted the country and, in the context of our long-standing partnership, will continue to assist Egypt in addressing these threats to its security."
The National Defense Council, which includes top military and public officials and is headed by President Abdel-Fattah el-Sissi, is to hold an emergency meeting in the coming hours, Ahram Online reported.
Later Wednesday, security officials said special forces killed nine members of the outlawed Muslim Brotherhood, including a former member of parliament, Nasr al-Hafi, during a raid on a Cairo apartment. It was not immediately clear whether the raid was related to the assassination or the checkpoint attacks. The Brotherhood denied involvement in the attacks.
The Interior Ministry identified the dead as fugitive Muslim Brotherhood leaders who had been hatching terrorist plots, including two people previously sentenced to death.
Late Wednesday, the Muslim Brotherhood accused the government of "executing" its leaders "in cold blood" and called for a rebellion against el-Sissi.
Sinai has been the site of several terror attacks against tourists and other targets in recent years. In 2012, a militant attack along the Egyptian-Israeli border left 16 Egyptian soldiers dead. The area, which borders Gaza and Israel, became more unstable after Islamist President Mohammed Morsi was driven from power a year later.
On Monday, the terror campaign spread to Cairo when Egypt's top prosecutor, Hisham Barakat, was assassinated. That led el-Sissi to promise a more intense crackdown on militants.
Police said weapons, cash and memory cards seized in Wednesday's Cairo raid would be used in the investigation of the Barakat's slaying.
Security forces have arrested 20 people accused of being behind a Facebook page – The Popular Resistance – that claimed responsibility for the assassination, Al Ahram Arabic reported Wednesday.
Province of Sinai was previously called Ansar Beit al-Maqdis (Champions of Jerusalem), but changed its name in November and pledged allegiance to the Islamic State.
The group, which was founded after Morsi's fall, had originally targeted Israeli border installations. More recently it has targeted Egyptian forces, killing hundreds of soldiers and police officers.
Posted by Women Against Shariah on Wednesday, July 1, 2015
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