The Moroccan Association for Human Rights released a report on Wednesday putting the death toll from last month's attempt by hundreds of migrants to storm the border between the north African kingdom and the Spanish enclave of Melilla higher than the official government tally.
The human rights watchdog, known as AMDH, said at least 27 people, mostly from Sudan, South Sudan and Chad, died in the attempt, with that number likely, to rise as many more suffered severe injuries and 64 people remained missing.
The Moroccan government has previously reported 23 deaths in the June 24 border storming.
AMDH Nador official Omar Naji said that Moroccan and Spanish authorities used smoke bombs and tear gas to disperse the migrants, who had gathered at the BarrioChino crossing area, which separates the Moroccan city of Nador from Melilla, leading to many dying of asphyxiation, although autopsies have not yet been carried out.
Other people, the group said, died in a stampede caused by the smoke and ensuing panic.
In addition to the deaths, 200 Moroccan and Spanish law enforcement officers and more than 70 civilians were injured in the melee.
AMDH Nador section President Mohammed Amine also said 64 people remained missing as of last Friday.
The group released its preliminary report on Wednesday, saying it was based on an investigation conducted by its affiliate in Nador.
The report said around 1,500 migrants and asylum-seekers departed that day from nearby forests and arrived at the BarrioChino crossing area at around 9 a.m.
There they tried to open the main gate and started climbing the checkpoints.
At that moment, Moroccan authorities began throwing stones and smoke bombs at the migrants, causing many to die of suffocation.
Those who tried to escape and desperately reach the fence perished in a stampede that was made worse by the heavy use of tear gas, it added.
It said Moroccan officers did not use lethal force but some beat wounded migrants lying on the ground.