James Reynolds: The government has gone on the offensive

The government declared the strike illegal in two important sectors, telecommunications and health, and ordered the army to occupy the country's oil refineries, where workers had threatened to stop production.

Since around 600,000 state workers began striking on Wednesday, the action has had a considerable effect throughout Colombia. Schools and courts have remained closed and hospitals have been treating emergency cases only.

Striking oil workers had threatened to stop production completely as the strike progressed. This would have left the country with reserves lasting less than a week.

The BBC South American Correspondent, James Reynolds, says by occupying the refineries, the government has taken away the strikers' biggest threat.

The strikers say that Andres Pastrana's economic austerity measures are unfair and that a wage rise offered by the government is insufficient.

The government says it will negotiate with the workers, but it will not change its economic policy. The government will hope to persuade the majority of the striking workers to go back to work over the next few days.