Egypt declares a three-month-long state of emergency as it begins to bury the more than 30 security personnel killed in two attacks on Friday. (Reuters)

More than two dozen Egyptian soldiers were killed in a car bomb attack at a military checkpoint in the restive Sinai Peninsula on Friday, marking one of the deadliest insurgent actions in the country in years, even as authorities have vowed to crack down on militancy here.

A vehicle packed with explosives detonated at a checkpoint near the coastal village of al-Kharuba, about 200 miles east of Cairo, on Friday afternoon, destroying an armored vehicle and scattering body parts onto the road, witnesses said.

At least 25 soldiers were killed and 26 others wounded in the blast in North Sinai governorate, according to Egyptian state television. The death toll makes it the bloodiest day for army personnel here in decades and underscores the continued ability of Egyptian insurgents to strike at security forces.

The military’s response to the bombing was swift, residents said. Almost immediately, security forces closed major roads in North Sinai and established perimeters around towns and cities, they said.

Witnesses also reported seeing army helicopters ferrying the wounded from the checkpoint, which is located outside the volatile city of Sheikh Zuwaid. Other residents said they saw fighter jets overhead.

In this photo provided by Egypt's state news agency MENA, Egypt's President Abdel-Fattah el-Sissi, center, holds an emergency meeting of the National Defense Council with top officials after an attack in the Sinai Peninsula, in Cairo Friday. (AP/AP)

Hundreds of soldiers and police officers have been killed in militant attacks since the army staged a coup against elected president and former Muslim Brotherhood leader Mohamed Morsi in July 2013.

Egyptian President Abdel Fatah al-Sissi called an urgent meeting of the National Defense Council, a consortium of top military, intelligence and cabinet officials, to discuss the attack, Egypt’s official news agency reported.

Sissi, a former defense minister and career military intelligence officer, is likely to come under considerable domestic pressure to respond forcefully to the attack. Since ousting Morsi, Sissi has portrayed himself as a strongman engaged in Egypt’s own “war on terror.” But his government has also rounded up thousands of dissidents and political activists without links to terrorism.

For years, the army has waged a security campaign in North Sinai in a bid to flush out the militant groups that have flourished there since the 2011 uprising that toppled President Hosni Mubarak. But residents say the army has conducted a repressive campaign that has killed civilians while failing to contain the Islamist extremists.

Immediately after the 2011 revolt, Sinai-based militant groups used the area to launch cross-border attacks against
Israel. The Sinai, whose population of Bedouin tribes views the central government in Cairo with suspicion, shares a border with Israel and the Hamas-run Gaza Strip, and has long been a conduit for networks that smuggle weapons and drugs.

But a government crackdown on the Muslim Brotherhood and the brutal dismantling of a pro-Morsi protest camp in Cairo in August 2012 — in which roughly 1,000 protesters were killed — spurred the militants to intensify their attacks on Egyptian security personnel.

The most formidable of the groups is Ansar Bayt al-Maqdis, which has expanded its attacks from the Sinai Peninsula to security installations on the Egyptian mainland and in the capital, Cairo.

Relatives of leaders and fighters in Ansar Bayt al-Maqdis say the group is made up mostly of Bedouins from North Sinai. While the group has praised the Islamic State on jihadist forums, North Sinai residents say there is little evidence that there are foreign fighters operating there.

The U.S. State Department released a statement Friday denouncing the attack.

“The United States strongly condemns the terrorist attack that targeted a military checkpoint in the Sinai near al-Arish, and killed tens of Egyptian soldiers and injured dozens,” State Department spokeswoman Jen Psaki said in the statement. “The United States continues to support the Egyptian government’s efforts to counter the threat of terrorism in Egypt as part of our commitment to the strategic partnership between our two countries.”

Egypt’s government has called on the United States to resume the $1.5 billion annual military aid program that was partially suspended after Morsi’s ouster. Egypt says it needs the assistance to battle the militants in Sinai.

U.S. Secretary of State John F. Kerry has sought to reassure Sissi that the United States will soon approve deliveries of Apache helicopters that had been halted as a result of the increasingly repressive political climate in Egypt.

Muhamed Sabry in el-Arish and Heba Habib in Cairo contributed to this report.