Hundreds of Moroccans have attended a vigil in the capital Rabat for two Scandinavian tourists found murdered in the Atlas mountains on Monday.
Holding signs saying "sorry", they gathered to remember Maren Ueland, 28, and Louisa Vesterager Jespersen, 24, at the embassies of Norway and Denmark.
On Friday Norwegian police said a video appearing to show one of the tourists being beheaded was likely to be real.
Four suspects aged between 25 and 33 have been arrested.
They pledged allegiance to the Islamic State group in a video made last week, police said. In the video, they said the murders were revenge for events in Syria.
Nine more arrests were made on Thursday and Friday for suspected links to the perpetrators, Moroccan officials said.
In Rabat a minute's silence was held with Danish and Norwegian diplomats present.
Hundreds more people attended a vigil in the southern village of Imlil, near where the women's bodies were found, and flowers were also laid in the city of Marrakesh.
Who were the victims?
Ms Jespersen, who was 24 and from Denmark, and 28-year-old Norwegian Ms Ueland had been studying outdoor activities at the University of Southeastern Norway.
They had arrived on a month-long holiday in Morocco on 9 December and had travelled to the foothills of Mount Toubkal, North Africa's highest peak, 10km (6 miles) from Imlil.
Their bodies were found in their tent.
Both women had taken full precautions ahead of their trip, Maren Ueland's mother said.