At least 16 people, including 13 policemen, were injured in an explosion Saturday outside a police training center in the Nile Delta city of Tanta, Egypt's interior ministry said.
The ministry, which is in charge of security, said the blast was caused by a bomb planted in a motorcycle parked near the police center. In addition to the police officers, the explosion wounded three civilians.
Louwaa el Thawra, or the Revolution Brigade, claimed responsibility for the attack on social media.
The Egyptian government is struggling to counter an increasingly violent insurgency in the Sinai Peninsula targeting Egyptian police and security forces. Hundreds of policemen and soldiers have been killed.
Several militant groups, including Ansar Beit al-Maqdis, which has pledged allegiance to the Islamic State group, control large swaths of the Sinai, which borders the Gaza Strip and Israel, independent of authorities in Cairo.
The militant campaign in the peninsula accelerated after the Egyptian military overthrew elected Islamist President Mohammed Morsi in 2013.