The United States’s FBI has joined the investigation into this week’s Nairobi blast, which officials say was likely caused by a fertiliser bomb.

A blast has struck a shopping centre in Nairobi, wounding 28 people but there was confusion over whether it was caused by a bomb or electrical fault.

A blast has ripped through a small shopping complex in central Nairobi and left at least 10 people wounded – the cause of the explosion is unknown.

Al-Qaeda allied Islamist gunmen have seized the key town of Dhusamareb in Somalia, as al-Shabab commanders call on fighters to intensify attacks.

Reports have surfaced that Australian Special Forces are allegedly gathering intelligence in several African countries.