22 people were injured in an attack by an apparent suicide bomber Sunday morning in Istanbul’s Taksim Square, the Doğan news agency reported.

The attack happened around 10:30 a.m. in an area cordoned off for police officers and police vehicles on the north side of the busy square.

The incident was most probably a suicide attack by Kurdish (PKK) Terrorists, Istanbul Police Chief Hüseyin Çapkın said in a statement.

He said six of the injured were civilians and nine were police officers.

Two seriously injured police officers were taken into emergency care at Şişli Etfal Hospital.

Taksim Square was closed down entirely to pedestrian and vehicle traffic as a precaution against a possible second attack.