About 600 African migrants in Algeria were allegedly abandoned in the desert before being rescued.

“Three days ago a first wave of 180 from Niger arrived in (the northern Nigerien city of) Agadez followed by another wave of at least 400 foreigners,” a local official.

The official, who spoke on condition of anonymity, said the migrants, including children and many women, had been “abandoned” in “the usual atrocious conditions near the border with Niger.

“According to the migrants, they were taken close to the border and dumped. Left with a minimum of food and water” they then “walked a good 50 kilometres (30 miles) before being rescued”.

Some of the migrants were now sick, he said, adding that all were being looked after by local and other west African authorities and the International Organization for Migration.

IOM Niger representative Giuseppe Loprete said in a tweet his agency had assisted 391 migrants of 16 nationalities including Ivorians, Senegalese, Guineans and Cameroonians “abandoned on the border with Niger and Algeria”.

Since the beginning of the year, the IOM has conducted 18 rescue operations and brought back around 3,000 people.

The IOM has reported a sharp rise in the number of migrants left to walk across the border between Algeria and Niger through the desert, up from 135 in May 2017 to 2,888 in April this year.