Supporters of former president Rodrigo Duterte continued to campaign for his release on Saturday, as they gathered in front of the International Criminal Court (ICC) detention facility in The Hague.

The supporters came from all over Europe, including Norway and Germany.

The gathering doubled as a celebration of Duterte's birthday. The former president turned 80 on Friday, March 28.

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As early as 10:00 a.m., former Justice Secretary Silvestre Bello was seen with the supporters. He confirmed that he had arrived in The Hague Saturday morning and was securing an appointment to visit the former president.

One group of Duterte supporters marched towards a larger park for an afternoon program, while the event continued near the detention facility with speeches from Atty. Harry Roque and Senator Robin Padilla.

Duterte's arrest on March 11 and rapid handover to the international tribunal came on the heels of his family's bitter falling out with his successor, President Ferdinand Marcos Jr.

His family and supporters gathered in The Hague on Friday to protest against his detention on a charge of crimes against humanity.

Duterte could spend the remainder of his life in jail if convicted at the ICC of the charge tied to his "war on drugs" in which thousands were killed. -- with Agence France-Presse