Egypt's Islamic State affiliate claimed responsibility for a wave of attacks Wednesday in the Sinai Peninsula that security officials said killed at least 20 soldiers.
The attacks against multiple military checkpoints included a suicide bombing near the town of Sheikh Zuweid.
An Islamic State group statement said the militants hit 15 different checkpoints in the attack.
Islamist militants in Sinai have repeatedly gone after Egyptian security forces with bombings and shootings, particularly since the 2013 ouster of Islamist President Mohamed Morsi by then-army chief and current President Abdel Fattah El-Sissi.
The latest attacks come days after Egypt's top prosecutor Hisham Barakat was killed by a roadside bomb in Cairo.
Sissi responded Tuesday by vowing to strengthen anti-terrorism laws and blaming Morsi's outlawed Muslim Brotherhood for Barakat's death.
The prosecutor had overseen the cases against thousands of Islamists, who have been jailed and convicted in mass trials as part of a massive crackdown since Morsi was pushed from office.
Sissi did not give details of his planned reforms, saying they would be unveiled in the coming days.