This year's Rainbow Family Gathering hasn't officially started, but already law enforcement is cracking down on the event, which the U.S. Forest Service characterized on Tuesday as "unauthorized" and "unsanctioned."

In their daily update on the festival, the Forest Service reported that more than 2,600 people already had converged on the Malheur National Forest in eastern Oregon. As many as 20,000 campers are expected for the July 1-7 event.

So far, 8 arrests have been made, and 192 warning notices and 47 violation notices have been given out. In anticipation of more citations and arrests, federal prosecutors and judges are setting up a temporary court near the gathering site, which is happening in the Flagtail Meadow about 20 miles northwest of Seneca. The remote court will be able to handle everything from parking violations to drug offenses to minor assaults that arise at the festival.

It's not clear how the federal prosecutors will handle marijuana use at the event. Recreational marijuana is legal in Oregon but remains an illegal drug under federal law, and the national forest is federal land.

The gathering is organized by The Rainbow Family of Living Light, and according to the Forest Service, participants began arriving two weeks ago. More attendees are expected in the coming days, with crowds reaching a peak on July Fourth.

The group didn't apply for a permit to gather in Malheur National Forest, as is required for groups of 75 or more. The Forest Service instead has created a guide listing regulations and shared it with the Rainbow group while making it clear the agency will enforce its provisions.

The Rainbow Family is a loose-knit group of people without leadership or organization who participate in a national gathering once a year. Attendees come from across the country. Since 1972, the event has taken place on a different national forest during a two-week period surrounding the Fourth of July holiday. Last year it was held in Vermont.

While the gathering is meant to champion values of peace and love, it can have a dark side. The large number of attendees can strain local resources, particularly in a remote area where there isn't the infrastructure to deal with large groups, and past gatherings have included drug arrests and run-ins with police.

Officials are worried that the gathering in the Malheur National Forest could damage forage due to excessive trampling by attendees, though they won't be able to know the extent of the damage until after the event has ended.

The gathering isn't the only thing straining Forest Service resources. On Monday afternoon, a severe thunderstorm moved through the area, causing seven lightning-strike fires. Fire crews responded quickly and were able to contain all of the fires.

-- The Associated Press contributed to this report.

-- Grant Butler

503-221-8566; @grantbutler