The Pentagon said on Thursday it has started a new, "narrowly-scoped" review of a deadly 2017 ambush in Niger, in which four U.S. soldiers were killed, to see whether additional punishments were needed.

The ambush, carried out by a local Islamic State affiliate, brought increased scrutiny of the U.S. counter-terrorism mission in the West African country.

A Pentagon report released late last year found that a series of individual and organizational failures, including a lack of training and situational awareness, contributed to the ambush. While no punishments were made public, lawmakers have expressed concern that junior officers could be blamed for the incident.

"Acting Secretary (Patrick) Shanahan has initiated a new, narrowly-scoped review into the Niger incident," Pentagon spokeswoman Commander Candice Tresch said. She said a four-star flag officer would lead the review.

Some current and former officials have expressed surprise at the decision to take a fresh look at the incident, particularly after the amount of public scrutiny the previous report received.

President Donald Trump's handling of condolence messages to the families of the dead U.S. soldiers was criticized by lawmakers in Washington and raised the profile of the deadly incident.

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