Dutch police reportedly made two arrests after a performance by a Los Angeles-based rock band was canceled Wednesday night because of a threat to a Rotterdam, Netherlands, concert venue.

Authorities detained a Spaniard who was driving a van containing gas canisters just a few hundred yards from the venue. Further details on the second detainee were not available, but that arrest was reported by the Fiscal Times, which cited Dutch broadcaster NOS.

A report by a German news site suggested that the driver had been cleared of involvement in the terror threat.

Police spokesman Gijs van Nimwegen said an update on the investigation would be issued later Thursday.

The concert by the band Allah-Las in the port city of Rotterdam was called off Wednesday night after Dutch police learned about a possible threat to the concert. Rotterdam Mayor Ahmed Aboutaleb said the warning came from Spanish police.

Two hours later police detained the van driver for questioning.

Aboutaleb said late Wednesday it was too early to know if the driver was linked to the terror threat. But a Spanish counterterrorism official confirmed the van was not connected to last week's deadly vehicle attacks in Barcelona and Cambrils.

The official said Spain's Civil Guard received "an alert indicating the possibility of an attack in a concert that was going to take place in Rotterdam."

The Civil Guard shared the information with Dutch authorities Wednesday and was investigating the threat, said the source, who spoke anonymously because the Civil Guard was still probing the threat.

The Associated Press contributed to this report.