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Shiites in a southwestern Pakistani city hit by a brutal terror attack refused to bury their dead Friday in protest, demanding that the government do something to protect them from what has become a barrage of bombings and shootings against the minority Muslim sect.

The bombings Thursday in Quetta were the worst in a series of attacks across Pakistan that killed 120 people. It appeared to be the country's deadliest single day of violence in five years.

Most of the dead were Shiite Muslims killed in twin bombings at a billiards hall -- a frightening reminder that Sunni extremists are increasingly targeting them.

Members of the beleaguered Shiite community in Quetta laid about 50 of their dead out in the street Friday, saying they would not bury them until the government improves security in the area. Young Shiite men also set tires on fire and blocked a nearby road in protest.

"We want safety for our all sects, and all security measures should be taken for our safety, said Fida Hussain, a relative of one of the victims. "We will not bury them until the government fulfills all our demands."

The strike was the worst of three deadly bombings targeting Shiites and soldiers in Quetta, capital of the volatile Baluchistan province, and worshippers at a Sunni mosque in the northwest on the same day.

It appeared to be Pakistan's worst day of violence since October 2007, when 150 were killed in a bombing aimed at Pakistani politician Benazir Bhutto. She survived the blast but was assassinated two months later.

Five people who were wounded in the twin bombings at the billiards hall late Thursday died of their wounds overnight, said Quetta senior police official Hamid Shakeel, putting the death toll from that attack at 86.

The billiards hall bombing, in a Shiite area of the city, started with a suicide attack followed by a car bomb minutes later. Militants often use such staggered bombings to maximize the body count by targeting rescuers and others who rush to the scene after the first explosion to help.

On Friday, Shiite volunteers erected tents to keep bystanders away from the severely-damaged building, where the pool hall once occupied the basement.

Nearby resident Jan Ali described it as a neighborhood gathering spot where young and old often waited in line to play on its six tables. He rushed to the scene Thursday night after the blast.

"It was a scene like hell on earth," said Ali. "Rescue people were carrying out dead and injured, people bleeding and crying, and rushing them toward ambulances. I have never seen such a horrifying situation in my life."

One of those killed in the carnage was a young human rights activist named Irfan Ali.

"He was a very active, energetic activist," said Tahir Hussain, a lawyer and vice chairman of the Human Rights Commission of Pakistan's Baluchistan chapter. He said Ali had been associated with the HRCP for the last ten years, often writing about social issues and oppression of the Shiite Hazara community. Shiite Hazara migrated from Afghanistan more than a century ago and have been the targets of dozens of attacks over the past year, but Thursday's was by far the bloodiest.

Ali appeared to have been killed during the second explosion after he rushed to the scene to help, said Hussain. On his Twitter feed before his death, Ali wrote about Hazara families who were leaving the area in fear.

Many residents railed at the government for the repeated acts of violence.

"This government has totally failed in protecting us," said Abbas Ali, who was collecting items from the rubble of his nearby shop, also destroyed in the blast. "Somehow we will get compensation for our losses but those who have gone away will not come back."

Pakistan's minority Shiite Muslims have increasingly been targeted by radical Sunnis who consider them heretics. Lashkar-e-Jhangvi, a Sunni militant group with strong ties to the Pakistani Taliban, claimed responsibility for Thursday's attack.

Last year was the bloodiest year for Pakistan's Shiite community in living memory, said Human Rights Watch in a press release Thursday. According to the organization over 400 Shiites were killed in targeted attacks in 2012; over 120 of them died in Baluchistan.

In the other incident in Quetta, a bomb hidden in a bag went off near a vehicle carrying paramilitary soldiers elsewhere in the city, killing 12 people and wounding more than 40 others.

The United Baluch Army, a separatist group, claimed responsibility for the attack in calls to local journalists. Pakistan has faced a violent insurgency in Baluchistan for years from nationalists who demand greater autonomy and a larger share of the country's natural resources.

The third blast Thursday targeted a mosque in the northwestern Pakistani city of Mingora, killing 22 people and wounding more than 70. There was no immediate claim of responsibility for that explosion.