KABUL, Afghanistan — An Islamic State suicide bomber struck a Shiite cultural center in Kabul on Thursday, killing at least 41 people and underscoring the extremist group's growing reach in Afghanistan even as its self-styled caliphate in Iraq and Syria has been dismantled.

The attack may have targeted the pro-Iran Afghan Voice news agency housed in the two-story building. The Sunni extremists of IS view Shiite Muslims as apostates and have repeatedly attacked Afghanistan's Shiite minority and targets linked to neighboring Iran.

The attack wounded more than 80 people, many of whom suffered severe burns.

Local Shiite leader Abdul Hussain Ramazandada said the bomber slipped into an academic seminar at the center and blew himself up among the participants. More bombs went off just outside the center as people fled.

The IS-linked Aamaq news agency said four bombs were used in the assault, one strapped to the suicide attacker. It said the center was funded by Iran and used to propagate Shiite beliefs.

At nearby Istiqlal Hospital, Director Mohammed Sabir Nasib said the emergency room was overwhelmed. Additional doctors and nurses were called in to help. At the height of the crisis, more than 50 medics were working to save the wounded.

By late afternoon, Health Ministry spokesman Wahid Mujro said 41 people were dead and 84 others wounded.

The cultural center was housed in a simple building surrounded by mud-brick homes in the Shiite-dominated neighborhood of Dasht-e-Barchi, home to some of Kabul's poorest residents.

A senior member of the local Shiite clerical council, Mohammad Asif Mesbah, said the center may have been targeted because it houses Afghan Voice. The news agency's owner, Sayed Eissa Hussaini Mazari, is a strong proponent of Iran, and the agency's output is dominated by Iranian news.

The White House is condemning a "barbaric" attack. Press secretary Sarah Huckabee Sanders said in a statement that "The United States strongly condemns today's barbaric attack at a cultural and social center in Kabul, Afghanistan, and offers its deepest condolences to the victims and their families."

The White House earlier said that President Donald Trump was briefed on the Thursday's attack.

Sanders said "the United States stands firmly with the government and people of Afghanistan and will work closely with the National Unity Government to bring the perpetrators of this heinous attack to justice."