(CNN) -- Police in northern France moved in Wednesday on makeshift migrant camps near the port of Calais, prompting a standoff with the defiant residents -- many of whom have fled conflicts in Syria, Sudan and Eritrea. By late afternoon, a CNN producer observed that the migrants' tents had all been destroyed. One activist told CNN police were responsible. About a dozen police officers remained, along with 50 to 60 migrants who didn't know where to go. A local prefect reportedly told the migrants they can stay at the camp until Thursday. But Thursday is Ascension Day, a public holiday, so it's not clear if the migrants will be cleared out before Friday.
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NEW: Camps appear dismantled, but about 50 to 60 migrants remain at one
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Police are trying to shift migrants from makeshift camps near Calais
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The migrants don't want to leave, won't take steps to tackle a scabies outbreak, authorities say
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Calais is a magnet for migrants seeking to reach Britain or claim asylum in France
Syria
Adt said the makeshift camp where he is located housed about 600 people, roughly half of them @placeholder, and between 200 and 300 Eritrean and Sudanese.
Eritrea
Adt said the makeshift camp where he is located housed about 600 people, roughly half of them Syrian, and between 200 and 300 @placeholder and Sudanese.
Calais
Calais
"The situation in @placeholder is worsening in a deafening silence," it said.
Britain
About 550 of those migrants are living in makeshift camps, the letter said, having claimed asylum in France or waiting to attempt the crossing to @placeholder.