Two people were killed and more were injured in a knife attack at the Muslim Ismaili Centre in Lisbon on Tuesday, Anadolu News Agency reports.
Portuguese police say they shot the attacker, who was wielding a large knife, after he disobeyed their orders to stop attacking.
The shot wounded the attacker, who was arrested and hospitalised.
Portuguese Prime Minister, Antonio Costa, expressed his "solidarity and condolences to the Ismaili community and the families of the victims."
He said authorities are investigating the incident, and it is still "premature" to jump to any conclusions about the motivations of the attack.
The two victims were women, according to Portuguese broadcaster, RTP. One, 49, was the manager of the Aga Khan Foundation that helps refugees in Portugal. The other was a 24-year-old volunteer at the Centre.
RTP also reports that the attacker was from Afghanistan and that three of his daughters attended Portuguese classes at the Centre.
The Ismaili Centre released a statement saying they had no information about the causes of the attack and conveyed their condolences to the families of the victims.
Ismaili, a sect belonging to the Shia branch of Islam, emerged after the death of Imam Jafar Al-Sadiq in 765.
There are an estimated 12 to 15 million Ismailis living in more than 25 countries around the world.
READ: Documentary film 'Brazilian Palestine' boosts the Palestinian cause