Suicide bombers attacked the offices of a top Pakistani official in the northwestern city of Peshawar on Monday, killing five people in the latest high-profile attack as the country prepares to hold elections.
Mutahir Zeb, the government's representative in the semi-autonomous tribal district of Khyber, escaped unhurt but his deputy was wounded in the attack on the sprawling compound.
There was no claim of responsibility. The military has long been fighting Taliban and other Islamist insurgents in Khyber, which straddles a key NATO supply route into Afghanistan, where US-led combat troops are due to leave next year.
Five people were killed and seven others seriously wounded when two suicide bombers blew themselves up at the complex, which contains Zeb's office, cells where police detain suspected militants and residential quarters, officials said.
"There were two suicide bombers. One blew himself up at the gate and the other inside the control room of the main office," said Peshawar bomb disposal chief Shafqat Malik.
"They were carrying up to eight kilos of explosives. Security officials have cleared the main office and a search is still going on in the residential area," Malik added. Witnesses had said there were three attackers.
Zeb's deputy, Khalid Mumtaz Kundi, who had been visiting from Khyber was wounded and evacuated to a military hospital, officials said.
Jamal Shah, spokesman for the main government-run Lady Reading Hospital, said seven people had been admitted with serious injuries.
He said four security officials and a civilian man aged around 60 were killed.
Some officials suggested the militants staged the attack to free detainees and unconfirmed reports indicated that some prisoners may have escaped.
Muhammad Iqbal Afridi, local leader in the opposition Pakistan Tehreek-e-Insaf party headed by retired cricket star Imran Khan, said he heard heavy gunfire.
"We were inside the office when we heard gun shots. Suddenly firing started and then they hurled some grenades," Afridi told AFP.
"Then there was intense exchange of firing between the militants and the security forces. Later, security forces evacuated us from the building. While leaving, I saw two dead bodies and blood everywhere," he added.
Violence has increased in the northwest in recent months as Pakistan prepares to hold historic general elections by mid-May, which will mark the first time an elected civilian government completes a full-term in office.
On Friday, Ameer Haider Khan Hoti, the chief minister of Khyber Pakhtunkhwa, the northwestern province of which Peshawar is the capital, escaped a Taliban assassination attempt en route to a political rally in the town of Mardan.
On December 22, the Pakistani Taliban claimed the assassination of Hoti's deputy, Bashir Bilour, in a suicide bombing at a political meeting in Peshawar.
In the southwest, a massive bomb attack killed 81 members of the minority Shiite Muslim Hazara community in the city of Quetta on Saturday.
On January 10, suicide bombers killed 92 people at a snooker hall in another Hazara part of Quetta, the deadliest single attack on Shiites in Pakistan, where rights activists say sectarian violence has reached record levels.