US Secretary of State Antony Blinken has said Washington has urged Israel to carry out a swift, thorough and impartial investigation into an Israeli airstrike that killed seven people working for the World Central Kitchen charity in Gaza, Reuters reports.

“We’ve spoken directly to the Israeli government about this particular incident. We’ve urged a swift, thorough and impartial investigation,” Blinken told reporters at a press conference in Paris, adding that humanitarian workers have to be protected.

“These people are heroes, they run into the fire, not away from it,” he said of the NGO workers killed in the strike. “We shouldn’t have a situation where people who are simply trying to help their fellow human beings are themselves at grave risk.”