MONTREAL - Two people were arrested for drug-related charges at Montreal's annual Bal en Blanc overnight, which ended at noon on Easter Monday after 15 hours of dancing.

About 15,000 fans of house, electro, trans and other such beats took over the Palais de Congres starting at 9 p.m. on Sunday, many shelling out $137 at the door.

In earlier years, the event was associated with massive consumption of ecstasy and other illegal drugs but such substances are now heavily policed, and all entering the dance were subject to search. 

In some years a dozen-or-so attendees were typically arrested for drug possession and other offenses but last year there were no arrests.

Partygoers were encouraged, but not required, to wear white. Those who do will be, "radiant, resplendent and irresistible," according to the event's site.

Organizers of the 18th-annual event revived the best-costume prize in an attempt to encourage extravagant clothing.

The 15 DJs for this year's event included Jacques Lu Cont and Danny Tenaglia, Armin Van Buuren, Ferry Corsten and Markus Schulz.