The Pakistani army's top surgeon has been killed by a suicide attack in the city of Rawalpindi, the military says.
Rawalpindi has been regularly hit by violence
Lt Gen Mushtaq Baig was one of at least eight people killed by the attacker, who also died.
Gen Baig is the highest ranking officer to be killed in Pakistan since the 9/11 attacks on the World Trade Centre.
In a separate incident, military officials say that at least four people have been killed in a grenade attack in the north-western town of Mansehra.
The violence in Rawalpindi is the latest in a series of major attacks there over the past year.
Lt Gen Mushtaq Baig - his driver and guard were also killed
Former Prime Minister Benazir Bhutto was killed in a blast in the city in December that left more than 20 other people dead.
The Pakistani military's headquarters is in Rawalpindi. The military and security agencies have borne the brunt of the violence there since the middle of last year.
A suicide attacker targeted a military bus in Rawalpindi on 4 February, leaving at least six people dead.
The BBC's Syed Shoaib Hasan in Islamabad says that Monday's incident is the second attack against army medical personnel this year, and the first since general elections were held last week.
The army says that Gen Baig's driver and guard were also killed in the bombing.
The bomb was detonated outside an office of the government's national data registration agency, on a main road that was busy with traffic. At least 20 people were injured, the interior ministry said.
A suicide attack in Rawalpindi on 4 February left at least six dead
"The bomber was apparently on foot and as the car stopped on the main mall road, he hit it," senior city government officer, Irfan Ellahi, told Reuters news agency.
In the incident in Mansehra, attackers stormed the office of the British-run non-governmental organisation, Plan International, and fled in two cars after setting the premises ablaze.
At least 10 people were injured in addition to the four Pakistani nationals who were killed. Earlier reports said that six people had died.
Plan International - based in the south of England - has been active in the area for 12 years in the fields of education, health and development.
"We have immediately closed our operations across Pakistan and dispatched a security team to the area. Counselling will be provided for those affected by the tragedy," Plan International Chief Executive Tom Miller said.
He said a motive for the attack was unknown.
Hundreds of people have been killed in suicide attacks in Pakistan over the past year.
Our correspondent says that the attacks appear to be part of a campaign by pro-Taleban militants to target military personnel in retaliation for army operations in Pakistan's north-western tribal areas - said to be a safe haven for the Taleban and al-Qaeda.