ROTTERDAM, Netherlands (AP) — Dutch police were continuing investigations Thursday into a threat to a concert venue that prompted the cancellation of a show by an American rock band, as well as into the driver of a Spain-registered van found to contain gas canisters just a few hundred meters (yards) from the venue.

Spokesman Gijs van Nimwegen said police would issue an update on the investigation early Thursday.

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

Two hours later police detained the driver of the van for questioning.

Aboutaleb said late Wednesday it was too early to know if the Spanish van was linked to the terror threat to the concert.

A Spanish counterterrorism official said the van is not connected to the vehicle attacks that killed 15 people in Spain last week.

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 is still probing the threat.