At least 11 students have been killed and about 20 hurt in a blast on a bus at a university for women in the western Pakistani city of Quetta.
A homemade bomb had been planted on the bus, police say.
Later gunmen attacked the hospital where the victims were being treated. A senior city official is reported to have been killed.
Quetta is the capital of Balochistan province, which has seen a surge in militant violence in recent months.
Some attacks are carried out by separatists and others by Islamists who oppose women's education.
In the latest, the students were about to go home when the explosion occurred.
"It was an improvised explosive device placed in the women university bus," police chief Zubair Mahmood said.
Hospital sources say some of the wounded are in critical condition.
Later another explosion rocked the medical centre where the students were being treated,
Militants armed with grenades were positioned there and exchanged fire with members of the security forces who rushed to the scene, police say.
Pakistan TV says a senior Quetta official, Abdul Mansoor Khan, who had gone to the hospital to visit the wounded students, was killed in the stand-off. There are fears of more casualties.
No group has said it carried out either attack.
The violence came hours after militants carried out a rocket attack against a historic home in the Ziarat area of Balochistan, which was used by Pakistan's founding father Muhammad Ali Jinnah.
The house is said to have been severely damaged.
Last month the Taliban killed at least 11 people in an attack on security forces in Quetta.