FREETOWN, Sierra Leone (AP) — The president of Sierra Leone has declared a public health emergency as the Ebola crisis deepens across West Africa.

The announcement from President Ernest Bai Koroma comes as neighboring Liberia also ramps up efforts to slow the virulent disease's spread.

Ebola has been blamed for more than 670 deaths in four West African countries this year, and has shown no signs of slowing down in Liberia and Sierra Leone.

Sierra Leone's leader says police and military would be aiding health workers, and homes with Ebola patients will be quarantined. He says house-to-house searches will be used to trace those who may have come into contact with sick people.

Koroma has declared Monday as a "National Stay Home Day" in hopes of stopping Ebola's spread.

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