The gunmen were said to have failed to free a captured militant
At least five people have been killed after gunmen attacked a hospital in the eastern Pakistani city of Lahore.
Dressed in police uniforms, up to four gunmen briefly seized hostages at the hospital, before escaping.
Dozens of people wounded in Friday's attacks on two mosques in the city were being treated in the facility at the time of the assault.
The authorities said they were pursuing the suspects after one was wounded in an exchange of gunfire with police.
Earlier the police said that up to eight people had been killed in the attack.
The gunmen were said to have failed in an attempt to reach a captured militant, injured in the mosque attacks, who was being treated at the hospital.
"The operation is over," an official, Shafiq Gujar, told AFP news agency. "It appears the attackers wanted to kill or release the accused."
Javed Ikram, chief executive of Jinnah hospital, told Reuters news agency that the gunmen had "barged into the hospital building and opened indiscriminate fire".
They were wearing police uniforms, and opened fire on the nine policemen who were guarding the captured militant, killing at least four of them, officials said.
Six people, including a woman and her four-month-old baby, were injured in the attack, police said.
Pakistan's Prime Minister Yusuf Raza Gilani has condemned the attack.
"Such inhuman act of brutality could only be conducted by those who neither believe in humanity not any religion," Mr Gilani said.
The gunmen fled after this latest attack, police said.
"They escaped from the scene," Lahore commissioner Khusro Pervez Khan told Reuters. "We are in hot pursuit. We are chasing them. One of them was wounded."
The assault came three days after suspected Sunni Muslim militants wearing suicide vests launched a gun and grenade attack on two Ahmadi prayer halls in Lahore and killed more than 80 worshippers from the minority religious community.
Lahore has been battered by a series of deadly attacks in the last year by militants who have declared war on both the government and minority groups in the country.