BRUSSELS (AP) 

Two Israeli soldiers were briefly detained at Belgium’s Tomorrowland music festival on suspicion of involvement in war crimes in Gaza, a pro-Palestinian organization said Monday.

The Hind Rajab Foundation, which advocates for accountability over alleged Israeli war crimes in Gaza, said the soldiers were taken into custody, formally questioned, and later released. The Belgian Federal Prosecutor’s Office has confirmed that a criminal investigation is underway.

“This marks the first time that a European country has formally arrested Israeli suspects linked to crimes in Gaza,” the foundation said in a statement.

The arrests followed a call by the group on Sunday for action against Israeli soldiers after the two men reportedly raised the flag of an Israeli infantry brigade at the festival the previous day. The group accused them of participating in military operations in Gaza.

Belgian authorities have not commented publicly on the identities of the soldiers or the specifics of the investigation.

The incident comes amid growing efforts by international activists and human rights groups to pursue legal cases against Israeli officials and soldiers over the ongoing war in Gaza, where more than 38,000 Palestinians have been killed since October, according to Gaza health authorities.