All 40 million residents of California have been ordered to stay at home indefinitely in a bid to battle the coronavirus pandemic in the nation’s most populous state.

The statewide directive, which Governor Gavin Newsom said goes into effect immediately is the most dramatic containment measure yet by a US state.

No end date has been set for the measure.

California has been among the worst hit by the virus, with at least 18 confirmed deaths so far, and around 1,000 tested positive.