A six-year-old boy was killed on Sunday in Egypt's Sinai Peninsula when a rocket hit his house, official security source told Xinhua.
The attack was an apparently targeting a security patrol passing near the house in northern Sinai city of Sheikh Zuweid.
The blast mistakenly hit the house and wounded other four persons belonging to the same family, the source added.
No group has yet claimed responsibility for the attack, and the wounded were transferred to the Arish Public Hospital.
The attack is likely a revenge for more than 50 of the militants killed last week by the armed forces in response to the killing of two police and military officers by gunmen.
Separately, four extremists were killed and 14 others were arrested in a security raid on several crime strongholds in North Sinai, the army spokesman Mohamed Samir said in a statement.
During the raid, 21 motorbikes and six vans used by the militants to attack the security forces were destroyed, the military statement added.
Militant attacks have mounted since the overthrow of the Islamist president Mohamed Morsi and the harsh crackdown over his supporters from July 2013. At least 1,000 were killed and thousands arrested, mostly Islamist protesters.
The attacks which usually target the security forces sometimes lead to civilian casualties.
On July 26, three civilians including two children were killed and nine others injured as a mortar round was launched by extremist militant groups and mistakenly hit two houses at al- Joura town south of Sheikh Zuweid.
Sinai-based al-Qaida-inspired Ansar Bayt al-Maqdis group claimed responsibility for most of attacks against the security personnel.