Russian officials said Saturday evening a woman carrying an improvised explosive device intended to enter the Italian restaurant “Russian Balsy” in the center of Moscow, but after guards prevented her from entering, an explosion occurred.

According to a statement by the Russian National Committee on Counter-Terrorism, the woman, the restaurant guard, and one of the customers were killed in the blast, and at least 21 other people were injured.

The explosion took place near one of Stalin-era skyscrapers in central Moscow. Security forces have cordoned off the area, and Russian authorities have not yet announced the identities of the victims or the possible perpetrators of the attack.

The Kommersant newspaper reported that the target of the bombing was guests who were in the outdoor area of the restaurant.