Rights groups have called for emergency aid and shelter for migrants forced out of Tunisia's port city of Sfax, as dozens of people protested in Tunis in support of their plight.
Hundreds of migrants fled or were forced out of the country's second-largest city after racial tension flared following the July 3 killing of a Tunisian man in an altercation between locals and migrants.
Sfax is a departure point for many migrants from impoverished and war-torn countries seeking a better life in Europe by making a perilous Mediterranean crossing, often in makeshift boats.
Romdane Ben Amor, spokesman for the Tunisian Forum for Economic and Social Rights, or FTDES, said that between 100 and 150 migrants including women and children were still stuck at the border with Libya.
He said about 165 more migrants had been picked up near the border with Algeria.
“Migrants are transferred from one place to another while other groups hide out in the wild in catastrophic conditions for fear of being detected and suffering the same fate as those stranded on the borders,” Mr Ben Amor said.
He called for emergency accommodation to be given to the migrants and said the authorities must send “a clear message” to Tunisian citizens to help them, regardless of their status.
About 100 protesters demonstrated on Friday evening in Tunis expressing their “solidarity with undocumented migrants”.
Meanwhile the head of a Cameroonian association claimed police had carried out “arbitrary arrests” of sub-Saharan Africans near the train station in Zarzis, south of Sfax.
“Around 300 have been arrested … just because of their skin colour,” said Eric Tchata, who posted online a video taken by a fellow Cameroonian purporting to show a group of people, including women and children, packed into a warehouse in Medenine, also south of Sfax.
Mr Ben Amor expressed fears that migrants could die if they are not immediately given aid and shelter, noting that the bodies of two had already been found.
Human Rights Watch has said the migrants have been left to fend for themselves without water or shelter in the border regions, where temperatures can rise over 40°C.