A suspect in the killings of two prominent Tunisian opposition figures has died in a clash with security forces, the interior ministry says.
Kamel Gadhgadhi was among seven militants killed in the raid on a house in Tunis.
One policeman also died in the operation, which began on Monday afternoon.
Tunisian security forces have fought a long campaign against Islamist militants over the past two years.
Gadhgadhi was wanted in connection with the killing of prominent left-wing politicians Chokri Belaid and Mohamed Brahmi last year.
The assassinations plunged Tunisia into a protracted political crisis, which the country has only now emerged from.
The raid comes a week after Tunisia's parliament adopted a new constitution - its first since the revolution three years ago.
The siege ended in dramatic style on Tuesday afternoon as special units from the National Guard stormed the house.
The Tunisian news agency TAP named the policeman who was killed as Atef Jebri, a 29-year-old corporal in the specialist unit in the National Guard.
One militant was arrested by police, TAP reported.
Police said the men were heavily armed.
"They had suicide bomb belts and explosive material," interior ministry spokesman Mohamed Ali Aroui told Reuters news agency.
More than 20 members of the Tunisian security forces were killed last year during operations against Islamist militants in the west of the country.
Analysts say politicians hope the new constitution will send out a message of stability after months of deadlock between Islamist and secular parties.
Ennahda, a moderate Islamist party, won the first democratic elections after long-time ruler Zine al-Abidine Ben Ali was forced from power in 2011.
But it has faced fierce opposition from secular groups, who have accused it being too close to militant organisations - charges it strongly denies.
Earlier this month, Ennahda Prime Minister Ali Larayedh stepped down and was replaced by Mehdi Jomaa, who heads the newly-appointed caretaker government.