The Nigerian military has reportedly killed the spokesman for the Islamist militant group Boko Haram.

A military spokesperson reported that two suspected members of Boko Haram were arrested, one of them believed to be the group's spokesman Abu Qaqa, who later died in custody after being shot while trying to escape, according to the BBC.

Boko Haram has denied the military's claim that Abu Qaqa has been killed, saying his identity had been mistaken. Given that Abu Qaqa is an alias, the spokesman's true identity may be harder to verify.

Boko Haram is a militant Islamist sect that aims to implement sharia law across Nigeria. It has claimed responsibility for a series of attacks on government and civilian targets, killing more than 900 people since 2009, according to Human Rights Watch.