The White House said on Friday that the US cannot confirm that the extremists responsible for bombing attacks in Yemen were affiliated to the Islamic State (IS) group.
Three bombing attacks rocked Yemen's capital Sanaa and Saada province during Friday prayers, killing at least 137 people and wounded some 350 others. The IS has claimed responsibility for the attacks.
"There is not, at this point, clear evidence of an operational link between these extremists in Yemen and ISIL fighters in Iraq and Syria," White House spokesperson Josh Earnest said, using an alternate acronym of the group.