LONDON (AP) — Three young children and a woman were injured Thursday in Dublin's city center in what Irish police have termed “a serious public order incident.”

A man also suffered injuries during the violence, which took place outside a school shortly after 1:30 p.m. Citing witnesses at the scene, Irish media said some of the casualties were hospitalized with suspected stab wounds.

Irish Prime Minister Leo Varadkar expressed his shock and said a suspect had been detained.

Police said one of the children, a girl, and a woman have sustained serious injuries. A man and the two other children sustained less serious injuries.

They added that they were “following a definite line of inquiry” and weren't looking for anyone else in connection with the violence.

Irish Justice Minister Helen McEntee said she was “deeply shocked” by the “appalling attack on three innocent children and a woman.”