A police office has been killed and at least 35 people wounded by a car bomb outside a police base in the Egyptian city of Ismailiya, officials say.
Intense gunfire was reported near the base after the car blew up.
Ismailiya and nearby areas have seen regular attacks on security personnel by Islamist militants.
The military has been carrying out a wide-ranging operation against militants in the neighbouring Sinai Peninsula.
The Sinai has grown increasingly unstable in recent years, triggered by the fall of President Hosni Mubarak.
His overthrow in February 2011 left the northern Sinai vulnerable to groups of jihadists, some with links to the Gaza Strip.
In September security forces launched an offensive against Islamist militants in the Sinai, but have suffered a spate of deadly bombings. In recent months some 100 members of the security forces have been killed.
Last month 11 soldiers were killed by a car bomb attack on a convoy of soldiers near the town of El-Arish.
Reproduced under licence from BBC News © 2013 BBC