However, match officials were quoted as saying that as many as 50,000 people were trying to attend Monday's match.
The ground held the opening ceremony and is due to host a semi-final and the Nations Cup final on Sunday, 6 February.
Sunday's quarter-final is now set to be played at the Ahmadou Ahidjo Stadium in Yaounde instead.
Condolences paid by Cameroon squad and Fifa
Cameroon captain Vincent Aboubakar issued a statement on behalf of the squad, saying the Indomitable Lions "deeply wail" after hearing about fatalities and injuries.
"To the families of the victims, [we] extend their heart-felt condolences and wish a speedy recovery to the injured," Aboubakar said.
"The Indomitable Lions urge the football fans in Cameroon and Africa to be highly disciplined and responsible within and outside the stadiums so that football matches in general and the 2021 Nations Cup remain festive moments.
"[We] also call for the preservation of security, brotherhood and shared happiness in the stadiums."
Football's world governing body Fifa has sent its "deepest condolences" to families and friends of the victims of a crush outside a stadium at the Africa Cup of Nations in Cameroon.
"Fifa sends its deepest condolences to the families and friends of the victims who lost their lives following the tragic incident that took place at Olembe Stadium," the statement from Fifa said.
"The thoughts and prayers of the global football community are with the victims, the ones who have been injured in this incident, and all the staff of both Caf and the Cameroonian Football Association (Fecafoot) at this difficult moment."
Cameroonian President Paul Biya ordered an investigation into the "tragic incident", while Caf is in in "constant communication" with the Cameroonian government and the local organizing committee and has also launched its own investigation.
'Families will cry' - Djemba-Djemba on difficult evening for Cameroon
Former Cameroon midfielder Eric Djemba-Djemba attended the last-16 game, which Cameroon won 2-1, and said news of the incident was "heart-breaking".
"It is very shocking as people were coming to the stadium to watch football, and people have died," the 40-year-old, who had a spell at Manchester United from 2003 to 2005, told the BBC World Service.
"We were inside and suddenly we heard people had died outside the stadium.
"It is the worst possible news because Cameroon did everything to play the tournament in Cameroon and built big stadiums. I think for me it is very sad.
"It will be difficult (for people to focus back on the tournament) because families will cry. Some people go to the stadium to support Cameroon, to support their team play, but it is the worst thing to happen to Cameroon."
Ivory Coast coach Patrice Beaumelle, whose side face Egypt in the last 16 on Wednesday, also sent his condolences to victims' families.
"The team is trying to stay focused on football although as human being they cannot be indifferent," Beaumelle said.