Nigeria, Sept. 13 -- The long-delayed trial of Khalid al-Barnawi, a suspected mastermind of the 2011 bombing of the United Nations building in Abuja, resumed on Friday at the Federal High Court in Abuja.

The attack, which occurred on 26 August in 2011, left at least 20 people dead and more than 70 others injured.

Mr Al-Barnawi is standing trial alongside four co-defendants accused of being involved in the bombing.

The co-defendants are Mohammed Bashir Saleh, Umar Mohammed Bello (also known as Datti), Mohammed Salisu and Yakubu Nuhu (also known as Bello Maishayi).

Mr Al-Barnawi, the prime suspect, was also accused of being a member of Ansaru, a Boko Haram breakaway faction said to be ideologically aligned with al-Qaeda in the Islamic M...