Islamist militants attacked military checkpoints in northern Sinai on 1 April, killing 15 soldiers and two civilians, and injuring more than 20.
Militants used rocket-propelled grenades and machine guns to carry out the attacks targeting military forces in Sheikh Zuweid and Rafah checkpoints in the northern Sinai Peninsula.
Clashes between the security forces and militants are continuing after military air raids are said to have killed 15 terrorists in the area. The Egyptian military said the number of casualties is expected to rise as many of the injuries are serious.
Egypt has been fighting Islamist militants in the Sinai for months, as radicals take advantage of a power vacuum that began with the Egyptian Revolution and the fall of dictator Hosni Mubarak in 2011 and gained momentum during the political turmoil of 2012 and 2013.
Sinai Province (previously known as Ansar Beit al-Maqdis), a prominent Islamist group that pledged allegiance to Islamic State (Isis) in 2014, has claimed responsibility for the latest attacks.
In January, it said it was responsible for simultaneous attacks on 12 military and police targets in Egypt's Sinai Peninsula that killed at least 26 people. The group also attacked military checkpoints in October 2014, killing 30 soldiers.
Egypt President Abdel Fattah Al-Sisi has pledged to combat terrorism in the Sinai, which has hit tourism due to the proximity of attacks to popular resorts such as Sharm el-Sheikh.
In January, three people were killed and 35 injured in an explosion near the police headquarters in central Cairo.