The Fed unexpectedly slashed its key rate on Monday to near zero and pledged to infuse liquidity into its bruising economy, while New Zealand, Australia and Japan also announced a round of monetary easing.

Still, U.S. futures plunged to hit their down limit on Monday as investors feared that the measures would not be sufficient to cushion the coronavirus' global economic damage.

"There's not much that policymakers can do to prevent a global recession developing over the coming months as the economic effects of the coronavirus begin to bite," said Neil Shearing, group chief economist at Capital Economics, in a note.

"History suggests that equity markets are only likely to bottom out when it becomes clear that the flow of new cases of the virus has peaked. Until this happens, we should expect stock markets to remain under pressure."

Malaysian equities plunged 4.8% to hit a near 10-year low and joined the rest of the region in bear market territory.

A bear market is confirmed when an index closes 20% or more below its most recent closing high.

Malayan Banking tumbled 7.5%, while hospital operator IHH Healthcare fell 7.1%.

The country on Friday flagged a $800 million hit to tourism due to the virus in the first two months of the year.

Philippine equities sank 7.9% in a curtailed trading session. The exchange has shortened trading hours as authorities placed the capital Manila under "community quarantine" for about a month starting Sunday to keep local transmission of the virus in check.

Singaporean shares eased 5.3% to end lower for a fourth-straight session, with financials and industrials leading declines.

Lender DBS Group Holdings fell 4% and conglomerate Jardine Matheson Holdings shed 7%.

Indonesian stocks lost 4.4%, with financials and consumer stocks being the biggest drags.

A Reuters polls suggests Bank Indonesia will likely make a second cut to its key policy rate in the year later in the week.

The Thai index tumbled 7.3%, as the country plans to shut schools, bars, theaters and other entertainment centres to curb the virus' spread.

By Arpit Nayak