Baghdad: A blast was heard in Baghdad late on Wednesday coming from the fortified Green Zone which houses government buildings and foreign embassies in the Iraqi capital, Reuters witnesses said.
The cause was not immediately clear.
An Iraqi soldier stationed in the Green Zone confirmed the noise originated from the zone but gave no other details.
Prime Minister Adel Abdul Mahdi on Wednesday declared a curfew in Baghdad until further notice after at least seven people were killed and more than 400 injured during two days of nationwide anti-government protests.
Earlier, Iraqi elite counter-terrorism service troops used live ammunition and tear gas to prevent protesters from breaking into Baghdad airport, police sources told Reuters.