Most border crossings in Liberia have been closed and communities hit by an Ebola outbreak face quarantine to try to halt the spread of the virus.
Screening centres are also being set up at the few major entry points that will remain open, such as the main airport.
Meanwhile, Nigeria largest's airline, Arik Air, has suspended all flights to Liberia and Sierra Leone after a man with Ebola flew to Nigeria last week.
The virus has killed at least 660 people in West Africa since February.
The outbreak began in southern Guinea and spread to Liberia and Sierra Leone. It is the world's deadliest so far.
Nigeria has put all its entry points on red alert after confirming that a Liberian man died of Ebola after arriving at Lagos airport on Tuesday.
Source: BBC