The UN refugee agency has criticised Cameroon for the forced return of hundreds of refugees to north-east Nigeria after they had fled from the Islamist Boko Haram insurgency.
The UNHCR said forced returns had “continued unabated” despite an agreement earlier this month.
Under the deal, any returns would be voluntary and only “when conditions were conducive”.
This year, more than 2,600 refugees have been forcibly returned to Nigeria.
Many are unable to go back to their villages in Borno state for security reasons and have ended up in camps for displaced people.
In some cases, the UNHCR said, people had been returned “without allowing them time to collect their belongings”.
UNHCR spokesman Babar Baloch spoke of “chaos” in the returns process and said “some women were forced to leave their young children behind in Cameroon, including a child less than three years old”.
Many of the returnees are now settled in the Banki camp for internally displaced people.
UNHCR staff also recorded about 17 people who claimed to be Cameroonian nationals, who it said had been deported by mistake to Banki.
It is common in the region to find people who have no documentary proof of their nationality.
The Cameroonian authorities have not responded to the UNCHR comments but have previously said Boko Haram militants have been entering the country disguised as refugees.
Militants have carried out a number of attacks in northern Cameroon in recent years, often using suicide bombers.
The UNHCR said forced return constitutes a serious violation of the 1951 Refugee Convention and the 1969 OAU Convention, both of which Cameroon has ratified, reports the BBC.
It called on Cameroon to honour its obligations under the conventions and continue keeping its borders open so as to allow access to territory and asylum procedures for people fleeing the Islamist insurgency.