LAHORE, Pakistan ? Gunmen fired Friday on an Islamic girls school, shattering windows, injuring one student and sending youngsters running for cover. Hours later, two men on a motorcycle tossed grenades at a Christian hospital.

Authorities said there was no indication the attacks were linked. However, Pakistan has been wracked by religious violence in recent years, much of it between rival Sunni and Shiite Muslim sects. This year, Christians also have been targeted.

A 12-year-old girl was hurt when bullets shattered the windows of the Jamia Mohammadia Binat-ul Islam school in Lahore. Police said she was treated at a hospital and released.

Students and teachers were shaken from their sleep when the shooting began early Friday, witnesses said.

There was no claim of responsibility for the attack.

“Dozens of bullets hit the wall of my house and school,” said Zahoor Ali Chishti, a cleric who runs the school, which has about 300 students aged 4 to 14. The girls study the Quran, the Muslim holy book.

Neighbors said they saw two men running away from the school toward a parked motorcycle. They sped off before authorities arrived.

Chishti suggested the attack could be linked to his candidacy for Parliament in next week’s elections. “Maybe one of my rival candidates did it to terrorize me,” he said.

Hundreds of miles away and hours later, two men on a motorcycle tossed grenades at a Christian Hospital in northwestern Pakistan near the Afghan border. There was minor damage but no injuries in the attack in Bannu, a region home to Muslim tribesmen.

The attack drew criticism from Christian leaders already angered by deadly assaults on Christians in Pakistan. Just last month, two gunmen killed seven workers at a Christian charity in Karachi.