* Security forces clash with militants operation
* Dozens of militants arrested
* Police general killed, nine wounded
* EU envoy meets govt, Brotherhood politician
By Asma Alsharif
KERDASA, Egypt Sept 19 (Reuters) - Egyptian security forces and militants exchanged fire as police stormed a town near Cairo dominated by Islamist supporters of ousted President Mohamed Mursi on Thursday, arresting dozens in an operation to reimpose state control.
A police general was shot dead and at least nine policemen and soldiers were wounded by a hand grenade in the clashes in Kerdasa, on the capital's western outskirts.
Dozens of police and army vehicles entered the town at daybreak in the second such raid this week to reassert government control over areas where Islamist sympathies run deep and hostility to the authorities has grown since the army overthrew and imprisoned Mursi on July 3.
There had been little or no sign of the security forces in Kerdasa since 11 police officers were killed in an attack on its main police station on Aug. 14.
The building was hit with rocket-propelled grenades and burned down after police had stormed pro-Mursi protest camps in Cairo that day and killed hundreds of his supporters.
"The security forces will not retreat until Kerdasa is cleansed of all terrorist and criminal nests," Interior Ministry spokesman Hany Abdel Latif said.
Special forces stormed a villa belonging to a man they said financed the police station attack, a Reuters witness said. The police used armoured vehicles to smash down the villa's gates before breaking in the door. But the man, whom they said was a member of Mursi's Muslim Brotherhood, was not there.
State news agency MENA said 65 people had been arrested so far. Dozens of weapons, including rocket-propelled grenades, were seized, state TV reported. A police officer said they had arrest warrants for 150 men in Kerdasa for suspected involvement in the attacks on the police station and a church in the area.
Members of the security forces in body armour and armed with automatic rifles fanned out through the town. Army checkpoints were set up on the roads into Kerdasa. Masked men set fire to tyres to try and obstruct the operation as it got under way.
Heavy gunfire was heard in the nearby village of Nahya as police chased a group of men into side streets, TV footage showed. In other footage, two detained men were shown cowering in a van weeping as policemen stood by, and a bearded man with his hands raised was led out of a building by police.
Officers entered buildings and courtyards with rifles raised and pointed them at windows. A helicopter hovered over Kerdasa's mostly deserted streets.
Militant attacks have been on the rise since the overthrow of Mursi, Egypt's first freely elected president.
With at least 2,000 Mursi supporters and many of the Brotherhood's leaders in jail, the prospects of any kind of political accommodation appear dim.
Analysts say that heightens the prospect of even more violence in a country with a history of Islamist militancy.
A European Union envoy told journalists reconciliation was "absolutely necessary, even if it looks extremely difficult".
Bernadino Leon, the envoy, was in Cairo to meet government officials and politicians including Amr Darrag, one of the few leading Brotherhood leaders who is neither in jail nor hiding.
State media have labelled the Brotherhood, the group that propelled Mursi to power last year, as an enemy of the state. The Brotherhood says it is committed to peaceful activism, saying the accusations against it aim to justify the clampdown.
The army-backed authorities say they are in a war on terror.
In a similar operation earlier this week, security forces moved into the town of Delga in the southern province of Minya - another area known for Islamist sympathies and a major theatre for an insurrection waged by Islamists in the 1990s.
The army is also mounting an operation in the Sinai Peninsula against al Qaeda-inspired groups. Shootings and bomb attacks have also taken place in the Nile Valley - two members of the armed forces were shot dead in the Nile Delta on Tuesday.
In Cairo on Thursday, explosives experts defused two primitive bombs on the metro underground railway.
Slightly easing a state of emergency imposed after the violence of Aug. 14, the government put back by an hour, to midnight, the start of an overnight curfew. A 7 p.m. curfew remains in place on Fridays, a traditional day of protest.
A pro-Mursi alliance, the National Coalition to Support Legitimacy, called for nationwide protests this Friday.