‘A Nigerian Shia group says more than 700 of its members are still unaccounted for a month after the deadly attacks by Nigerian forces against Shia Muslims in the northern city of Zaria.

In a statement released on Thursday, Ibrahim Musa, the spokesman for the Islamic Movement of Nigeria (IMN), whose leader Sheikh Ibrahim al-Zakzaky is in police custody, said about 730 people have gone missing since December 12, 2015.

“These missing people were either killed by the army or are in detention” but their “whereabouts are still unknown and undisclosed,” Musa said.’

Read more: Over 700 Shias missing after Nigeria army raids: Shia group