By Mary Manning

Published Tuesday, March 4, 2008 | 12:55 p.m.

Updated Thursday, Dec. 4, 2008 | 11:53 a.m.

Steve Marcus

A Clark County Fire truck is stationed outside the Excalibur after a guest reported a suspicious substance in a room Monday, March 4, 2008. The County's hazardous material unit and Metro Police responded but the substance was determined not to be harmful.

After a guest called the front desk at the Excalibur at 9:30 a.m. today, complaining of a white powder on the bedspread, Metro Police and Clark County Fire Department investigators discovered that the substance was harmless.

Once a dozen investigators — including a hazardous materials team — concluded their examination, the northwestern parking lot was reopened to the general public minutes after noon.

There is no danger to the tourists or the community of Las Vegas, Metro Police spokesman Bill Cassell said.

Yvette Monet, a spokesperson for the MGM Mirage, which owns the Excalibur, said that the investigation was confined to a single room in Tower two. The casino was never closed during the incident.

This is the second time a hazardous materials team has been called to the Excalibur in less than a week. On Friday a team cleared a room where Thomas Tholen, a cousin of 57-year-old Roger Von Bergendorff, stayed last week. Bergendorff is in a coma at a local hospital. Tholen discovered two vials of ricin, a biological toxin made from castor beans, and some of the beans in his cousin's off-Strip hotel room on Feb. 29.