brussels attacks
Brothers Ibrahim and Khalid El Bakraoui (L and C) died in the attacks at Brussels airport on 22 March 2016 when they detonated suicide vests. The third man, identified as Najim Laachraoui (R), has not yet been caught. CCTV

Turkish President Recep Tayyip Erdogan has said that his country previously deported Brussels suicide bomber Ibrahim al Bakraoui , and warned Belgian authorities that he was a terrorist.

Erdogan said that Turkish authorities deported the member of the cell who carried out terror attacks on Brussels airport and a metro station in the city, but Belgian security services failed to establish his terror links and subsequently released him.

''[The] Belgian embassy was notified on 14 July 2015 about the deportation of the attacker, who was later released in Belgium'' Erdogan said.

"Despite our warnings that this person was a foreign terrorist fighter, Belgium could not establish any links with terrorism."

Erdogan said that the militant, who he did not name, was arrested in Turkey's southeastern Gaziantep province in 2015. Presidential sources later confirmed to CNN Turk that the man was Ibrahim al-Bakraoui

In the attacks on Brussels' Zaventem Airport and a metro station in the centre of the city at least 31 people were killed and more than 200 injured. Belgian officials have identified the suicide bombers responsible for the attacks as 29-year-old Ibrahim and his 27-year-old brother Khalid.

Khalid was subject of an Interpol 'red notice', alerting police forces around the world that he was wanted on terrorism charges in Belgium. According to the notice, he was wanted since last August. There was no notice for his brother.

Belgian media reported that both were known to Belgian authorities for their involvement in organised crime.

A third suspect, named by Belgian media as Najim Laachraoui, remains on the run. Laachraoui appears in CCTV footage with the brothers in Brussels airport before the attacks. He is believed to have planted a third bomb at the airport, which failed to explode.

Israel's Haaretz newspaper reported that Belgian security services were provided with detailed information that terrorists planned to target Brussels airport and metro but failed to act.

The newspaper does not identify the source of the information, but claims that the attacks were planned in the Islamic State's Syrian headquarters, Raqqa.