The ministry said two attackers arrived in a commercial vehicle around 9:30 am (0630 GMT) "in front of the entrance gate of the General Directorate of Security of our Ministry of the Interior, and carried out a bomb attack."

"One of the terrorists blew himself up and the other was neutralized," the ministry added on social media, saying two officers received "minor injuries".

The targeted district is home to several other ministries and the Turkish parliament, which was due to reopen today with an address from President Recep Tayyip Erdogan, according to Turkish media.

TV channel NTV reported gunfire in the cordoned-off district, where emergency services were in attendance.

There was no immediate information on the assailants. Kurdish and far-left militant groups as well as the Islamic State group have carried out deadly attacks throughout the country in the past.

Television footage showed bomb squads working near a parked vehicle in the area, as police cordoned off access to the city center.

The two police officers were being treated in a hospital and were not in serious condition, media reports said.