Double suicide bombings struck the heart of Somalia’s capital over the weekend, killing at least 276 people and injuring more than 300 in what is being called the terror-torn country’s deadliest attack ever, authorities said.

An explosive-filled truck detonated on a crowded street in Mogadishu Saturday, destroying several buildings and setting nearby cars ablaze.

A short time later, a second car bomb exploded in the nearby Medina district, authorities said.

Somalia’s government has blamed the truck bombing on the al- aeda-affiliated al-Shabab Islamist extremist group.

The group has yet to claim responsibility but has carried out dozens of suicide bombings in its attempt to overthrow Somalia’s current government.

“They don’t care about the lives of Somali people, mothers, fathers and children,” Prime Minister Hassan Ali Khaire said of the attackers. “They have targeted the most populated area in Mogadishu, killing only civilians.”

Doctors and staff at area hospitals struggled to assist horribly wounded victims, many of whom were burned beyond recognition.

“This is really horrendous, unlike any other time in the past,” said Dr. Mohamed Yusuf, director of the Medina hospital.

“Nearly all of the wounded victims have serious wounds,” said nurse Samir Abdi. “Unspeakable horrors.”

Sirens continued to echo in the city throughout the day, as people dug through rubble, searching for missing relatives.

Angry protesters took to the streets after the attacks, congregating at the blast points and speaking out against the violence.

President Mohamed Abdullahi Mohamed declared three days of national mourning.

“We will observe three days of mourning for innocent victims. Flags will be flown at half-mast. Time to unite and pray together. Terror won’t win,” Mohamed said in a statement posted on the presidency’s official Twitter account Sunday.

World leaders spoke out against the terror attacks, with the United States condemning the bombing “in the strongest terms.”

The United States “will continue to stand with the Somali government, its people and our international allies to combat terrorism and support their efforts to achieve peace, security, and prosperity,” read a State Department memo.

Leaders from European countries also spoke out against the bloodshed.

“Solidarity with Somalia. Support to the African Union against Islamist terrorist groups. France stands by your side,” French President Emmanuel Macron tweeted.

With Wires