Alex Ritson

The US president had previously warned that he was ready to attack Islamists in Nigeria, accusing them of persecuting Christians, though the government in Abuja insists that innocent Muslims are also victims of IS.

Reverend Father Paul Ebu-Bedike is from the Catholic Diocese of Nui in southeastern Nigeria.

He said that US intervention was long overdue.

So what more do we know about the Islamic State fighters who were targeted?

Barry Marston is BBC Monitoring's jihadism analyst.

The Nigeria branch of the Islamic State is actually probably the most active of any of its worldwide branches.

It's been stepping up attacks over the last year.

It's claimed well over 300 attacks, including some very ambitious assaults on military bases across parts of the country.

But you could make the case that if the U.S.

was wanting to strike the Islamic State in Nigeria, it hit the wrong side of the country, because all of that activity has been right up in the northeastern corner of

The latest attacks were right on the other side of the country, about a thousand kilometers away in Sokoto state.

Now, the target seems to have been what is known as the Laka Ara group, which there have been unconfirmed reports that it may have pledged allegiance to the Islamic State.

But there really is nothing sort of out there in the public domain confirming that allegiance or connections between the two entities exist.

So we have been monitoring Islamic State affiliated channels that have actually been monitoring U.S.

military flights over the country over the past month.

And we'd noticed the prevalence of flights over the Sakoto region, as well as Borno areas where Islamic State has very well-known camps.

So it's entirely possible the U.S.

could be planning to follow up with attacks on these better established, better known Islamic State centres across Borno states, sort of based on this reconnaissance and movement of U.S.

planes.

Barry Marston from BBC Monitoring.