At least 43 people have been killed and many more have been wounded in an attack on a bus in the Pakistani city of Karachi.
The bus belonged to members of the Ismaili Shia Muslim sect and was targeted by attackers at the Safoora Chowk intersection in Karachi's eastern part on Wednesday.
Ghulam Haider Jamali, Sindh police chief, said officials believe there were six attackers, who approached the bus on three motorcycles.
Testimony from those who have seen the bus, and footage of it, suggests that the attackers boarded the bus and shot indiscriminately while inside.
Jamali said that those killed had been hit by 9mm gunfire, indicating that handguns had been used in the attack.
Pamphlets left at the scene of the attack claimed that it had been carried out by fighters allied to the Islamic State of Iraq and the Levant (ISIL) group.
"Oh soldiers of the [unbelievers]! We swear that we will make you and your families cry tears of blood and will not rest until we have cleansed this land of you and established sharia," read the pamphlet.
Jundullah, a Pakistani armed group that pledged allegiance to ISIL in November 2014, also claimed responsibility for Wednesday's attack.
In a statement published shortly after the killings, the Aga Khan, the spiritual leader of Ismaili Muslims, called the attack a "senseless act of violence against a peaceful community".
"My thoughts and prayers are with the victims and the families of those killed and wounded in the attack,” he said.
Following the attack, the bus was driven to the nearby Memon Medical Institute and Hospital with 62 people still inside - many of whom had already died.
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"When the bus came into the hospital, there were some people whose heads were hanging limply out of the windows," said a hospital official, on condition of anonymity.
Many of those injured were in critical condition, Salma Wahid, hospital official, told Al Jazeera.
"Their condition is serious and they were covered in blood when they came in," Wahid said, adding that many were unconscious when they were admitted.
Qaim Ali Shah, chief minister of the Sindh government, said he had ordered senior police officials to investigate the incident.
"I have taken it very seriously. I am terribly sorry that this nasty incident has taken place. Whoever it is, we have to detect the offence and take action against the culprits," he said shortly after the attack.
This is the fifth major attack against the Shia in Pakistan this year, with previous attacks including suicide attacks and bombings at Shia mosques in Rawalpindi, Islamabad, Peshawar, and Shikarpur.
Those attacks claimed the lives of at least 98 people.
Karachi, home to at least 20 million people, has often seen incidents of targeted attacks on political, ethnic and sectarian grounds, although violence has decreased since a paramilitary operation against criminals was launched in September 2013.
Source: Al Jazeera