A Nigerian court has convicted separatist leader Nnamdi Kanu on charges related to “terrorism” after a years-long trial.

In his ruling on Thursday, Nigerian Judge James Omotosho said prosecutors proved that Kanu’s broadcasts and orders to his now-banned Indigenous People of Biafra (IPOB) group incited deadly attacks on security forces and citizens in the southeast.

The violence was part of his push for an independent Biafra state for the ethnic Igbo-dominated region.

“His intention was quite clear, as he believed in violence. These threats of violence were nothing but terrorist acts,” Omotosho said.

Kanu, who has been in custody since his controversial re-arrest in Kenya in 2021, shouted angrily in objection to the proceedings and was ejected from court ahead of the ruling. He had argued that his unlawful extradition from Kenya undermined any chance of a fair trial.

Kanu pleaded not guilty in 2021 to seven charges that included “terrorism”, treason and perpetuating falsehoods against Nigeria’s former President Muhammadu Buhari.

Kanu was first arrested in 2015, but fled the country while on bail. His social media posts during his absence and his Radio Biafra broadcasts outraged the government, which said they encouraged attacks on security forces.

Ultimately, security agents brought Kanu to court in Abuja in June 2021 after detaining him in Kenya, where his lawyer alleged he was mistreated. Kenya has denied involvement.

In October 2021, Kanu’s lawyers argued that his statements on Radio Biafra shouldn’t be admissible in a Nigerian court since they were made in London.

“I can’t see how someone would make a statement in London and it becomes a triable offence in this country,” Kanu’s lawyer Ifeanyi Ejiofor told reporters at the time.

Kanu, a dual Nigerian-British citizen, started Radio Biafra – an obscure, London-based radio station – in 2009 after he left Nigeria to study economics and politics at the London Metropolitan University.

In one broadcast, Kanu said: “We have one thing in common, all of us that believe in Biafra, one thing we have in common, a pathological hatred for Nigeria. I cannot begin to put into words how much I hate Nigeria.”

IPOB wants a swathe of the southeast, the homeland of the Igbo ethnic group, to split from Nigeria. An attempt to secede in 1967 as the Republic of Biafra triggered a three-year civil war that killed more than one million people.