WASHINGTON — The United States on Wednesday expressed 'grave concern' after an airstrike in Ethiopia's war-torn northern region of Tigray killed as many as 30 people when it hit a market on Tuesday.

We strongly condemn this reprehensible act. There are also credible reports that security forces denied medical personnel access to the victims of this terrible attack.

"Denying victims urgently needed medical care is heinous and absolutely unacceptable. We urge the Ethiopian authorities to ensure full and unhindered medical access to the victims immediately. We also call for an urgent and independent investigation, as well as remedial action, to hold those responsible for this attack accountable," the US Department of State said in a statement.

"The United States again urges an immediate ceasefire in Tigray, unhindered humanitarian access, and protection for civilians," the statement added.

The bomb struck a market on the 33rd 'martyrs day' in Tigray — a date marking the Hawzen Massacre that killed more than 1,000 Tigrayan people at a market in Hawzen towards the end of the Ethiopian Civil War. Ethiopian Military spokesman Col. Getinet Adanesaid that reports of an aerial bombardment were "fake news."