The International Organization for Migration (IOM) on Thursday voiced alarm over reports of pushbacks and collective expulsions of migrants, in some cases violent, from Greece.

"IOM, together with partners, are closely monitoring the situation and have received reports of migrants being arbitrarily arrested in Greece and pushed back to Turkey and violence perpetrated against migrants by some border personnel," the global migration agency said in a statement.

"The Organization calls on Greek authorities to investigate these allegations and testimonies given by people forced to cross the Greece-Turkey border," it added.

IOM also said countries should refrain from deportations during the COVID-19 health crisis but could continue voluntary returns.

"Amid heightened health considerations, we urge states to refrain from securitizing borders and implementing migration practices that could compromise the human rights of migrants, including measures such as the construction of border walls, militarizing border patrols or increasing deportations."